In addition to the hormonal changes and the changes happening inside the body, females may also notice changes in their vaginal discharge. Vaginal discharge is a fluid—usually white or clear—that comes out of the vagina.

Most females have vaginal discharge. Increased vaginal discharge can be caused by normal menstrual cycle changes, vaginal infection, or cancer rare. If a female has more than her usual amount of vaginal discharge, she may need to see her health care provider.

To chart her menstrual cycle, a woman can simply record the day her period starts and when it ends on a paper or electronic calendar. Smartphone and computer applications that chart menstrual cycles are also available. Over time, this tracking will help a woman see what the typical amount of time between periods is, which can help her predict when her next period will start.

Tracking the menstrual cycle can provide useful information for conversations with health care providers. For example, a patient may want to discuss the length of her cycle or her experiences with pain or extreme bleeding during her cycle. In addition, tracking the cycle is key to predicting ovulation, which can inform decisions about when to have sex, whether the intent is to avoid pregnancy or become pregnant.

Women and couples become more familiar with the signs of ovulation and the pattern of the menstrual cycle to understand how to plan sexual activity to avoid pregnancy or become pregnant. Fertility awareness-based methods FABM involve a woman learning to recognize the signs of her fertile days, which are the days of each month in which she is most likely to become pregnant conceive.

Based on her intentions, she may plan to have unprotected sex during this time in order to conceive, or she may choose to avoid pregnancy by not having sex or by using a barrier birth control method, like condoms, during this time.

Infertility is defined as not being able to become pregnant after having regular intercourse sex without birth control after one year or after six months if a woman is 35 or older.

Infertility is common. Out of couples in the United States, about 12 to 13 of them have trouble becoming pregnant. About one-third of infertility cases are caused by fertility problems in women and another one-third of infertility cases are due to fertility problems in men.

The other cases are caused by a mixture of male and female problems or by problems that cannot be determined. Poverty levels were high with most of the residents surviving on less than a dollar a day.

Respondents received most of their information through school, non governmental organizations NGOs , family or friends. Friends were the most common source of information for women, who at times received accurate information from friends, more so than from school.

Commonly, when a girl first started getting her menses, other girls told her that this meant she could now become pregnant. As is clear in the quote from the following woman, confusion mixed with underlying shame made it hard to reach out to friends for information and support:.

I would want to hide it from her my friend because I feel embarrassed. It is just embarrassment because the first day I talked to her about it I did not know what was happening to me. I could hear us being taught but I did not think I had reached that age. So I was forced to ask her.

She explained to me and told me I had attained that age and so every month I would have my periods and in case I missed my periods any month it would mean I had become pregnant. Maria, 28, married woman, 2 children. Women also mentioned talking with other women about menstruation, and its link to fertility, most frequently co-wives or sisters.

I normally ask her co-wife because she gets pregnant frequently hence make her have many children. I do ask her why she gets pregnant like almost immediately after delivery.

And she tells me that immediately after delivery she gets her monthly period. I talk to her about such kinds of things and I tell her that after giving birth to my baby who is 8 years now, I stayed 4 years without getting my monthly periods Mona, 25, married woman, 3 children. Women who felt that they had not received information blamed lack of close female friends or relatives, for example, in the quote below where a woman lived with her grandmother and therefore did not have information until she learned about it in school.

The problem is that I grew up with my grandmother and she never told me anything about menstruation. At times a girl could soil her dress then I would ask to know what happened.

But the school contributed a lot in teaching me about menstruation. Akoth, 23, Married woman, 3 children. A few men discussed how they learned about menstruation from their wives. A few described how, since they had been married at such a young age, they were already married when their wives first experienced menses and they told their husbands about it, so they learned of it then too.

Other men mentioned male friends and elders as key sources of information. I asked one of my friends if women experience menses and he told me that women must experience menses.

Every month a woman must experience menses and a woman who is not experiencing menses could be having a problem, you need to take her for treatment. I then asked him that what problem could be there.

John, 25, married man, 1 child. One man discussed in detail the information that he had received in school, which was actually misinformation about the relationship between menstruation and pregnancy.

R: In school we were being taught during a subject called health science. We were told that when a woman is on her menses, a few days to end the menstrual cycle if she engages in sexual intercourse with a man then she can get pregnant… When she is about to clear her menses.

I: You were taught in health science that if a woman finished her menses immediately after that if she engages in sex then she can get pregnant? R: We usually talk, in fact even when this one began and went on for one week, I told him my period had gone on for a whole week in the previous month and this month I had not got my period.

He told me to just wait. R: No, he lives far. We meet once in a while. But when I first started having my period he knew the dates; if I told him he would know. After delivery I hear your cycle can change. R: He would tell me when I know my period is close I should not visit him [laughter] because anything can happen.

Another potential source of information about menstruation, especially the link between fertility and menstruation could have been at health facilities, or even at the time of antenatal care visits ANC or delivery.

However, in our study while most women were asked about their LMP during their first ANC visit, they received no other related information, even why they were being asked that question.

Younger women were more likely to go to their first ANC visit later in pregnancy, and they cited denial about being pregnant, fear of being scolded by staff or being attended to by male staff, and a general belief that people looked down upon them if they went to the health facility too early, as reasons not to go.

The reason why I feared to go for ANC when I was expecting my baby, is that there were male staff at the facility. I was imagining that I was going to find the same male staff there, so it was making me more worried.

When I was expecting baby in , I just remembered the male staff and it was not easy for me. But when I came I found there were some changes …The male staff were not there, there were sisters, and they were sisters that you can even share with them your ideas.

Auma, 21, married woman, 2 children. I went to the clinic later when the pregnancy was 5 months…. I was afraid because I was going to a certain clinic in Kibera and they were very harsh…The clinic staff, they wanted the exact date when one conceived, which I did not know.

And that is what made me fear. That is what made me take long I went after 3 months then stayed much longer before going back. Awino, 24, married woman, 2 children. Although most respondents knew there was a relationship between menstruation and pregnancy, accuracy of information was very poor.

A few respondents did generally have the correct information, however, they were a little unsure and hesitant about the exact details.

As one woman explained:. There are some days after your menses that you cannot get pregnant, they are called safe days something of the sort. Achieng, 31, married woman, 1 child.

Most respondents believed women could become pregnant during menstruation or in the few days before and after. She always tells me when she is experiencing menstrual cycle.

Ojwang, 25, married man, 1 child. Another man explained that he also believed women could become pregnant the few days before her menstruation, as well as during and after.

R: To get pregnant for a mother in that menstrual period, with my understanding it is before seeing that blood and after seeing that blood before seven days. R: It is that before the mother sees that blood, the blood will come and by that time it is still not bleeding and maybe you are having sex and it will find when that egg is mature and in that pregnancy maybe an outcome.

Sometimes the woman has experienced periods and has completed the periods, but before seven days after ending the periods, she can also conceive at that time. Odhiambo, 26, married man, 2 children. Interestingly, men and women acknowledged some confusion about the relationship between the timing of menstruation and when a woman could get pregnant, discussing how they had heard different information from various sources.

Some men are the ones who do say that if a woman is experiencing her menses that is the time he needs to have sex with her to make her pregnant and some are saying that when she is on her menses she is dirty, such that he cannot have sex with the woman.

Women also expressed fear and stigma about their menses, especially fear that it would occur while they were at school or other public settings. When we were going to school some girls could have blood stains at the back of their dresses and that used to worry me a lot.

There was a time when I had gone to visit my Aunt and it happened to me. I: You have said that whenever a girls dress would be stained at the back it would cause you a lot of worries. R: It was worrying because at times it could happen when you are in class and the boys would make fun of it so I used to imagine that the same thing would happen to me.

Mona, 25, married woman, 3 children. Many women tried to track their menstruation, primarily calendars. Some men and women both said that they memorized the date.

Some women specifically asked their partners to help them remember the date. Additionally, many women struggled with irregular periods and some stated that they did not know the date of their last menstrual period LMP when they became pregnant, highlighting the need for support for women in tracking their periods.

R: Safe days I think being a woman they know how to calculate this, they know the time they are safe.

R: It is important if you are free with your wife talking to her, both of you are free with each other and she can tell you anything on her body and you can also tell her anything on your body, but I think it is important for one to know. When you know time she is experiencing her menses, then you have sex and she get pregnant and you know that date she has gotten pregnant, you know there are women who are not even aware when they get pregnant and the pregnancy will come as a surprise to her until she is told by other women that are you pregnant and she will say that I am not pregnant.

One woman discussed that her husband thought she was using her period as an excuse and made her show him the evidence blood before believing her.

Women were interested in simple tools to track menstruation, and highlighted a need for privacy. Many women were interested in simple tools like a journal or calendar on paper that they could mark in, with some noting that illiterate women could potentially use that.

Some women already used their phones, by setting an alarm although other women felt that an alarm was a potential breach of privacy. Some had concerns of a phone because could easily be lost or stolen or that someone else could see phone, including children, who were seen as more technology savvy.

You know our kids nowadays they have become active especially on phones because they would want to know almost everything and they would want to know everything on the phone. Otieno, 35, married man, 5 children. Other respondents saw the benefit of a phone since it was something they already had and were using, and that it had the potential to provide other types of health related information as well.

A few respondents even gave suggestions about how a phone could be used to help women, as described below. Yes when you hear that alarm ringing in the phone and you see the picture of a moon indicating, it will act like a message, when you open that message you get all the information that you should be prepared like this, this is what the menstruation period says, you should act like this, you should be clean, pads it tells you like that.

Oguda, 26, married man, 2 children. Overall, however, due to privacy concerns and lack of comfort, most female respondents felt that something like a calendar that they could mark more privately and more easily hide would be more beneficial to them.

Additionally, few respondents had smart phones, and therefore even if there was a mobile option, it would have to be very simple. Notably, a few of the adolescent mothers worried that their parents would be suspicious of something unusual on their mobile phones, and therefore felt that it was not a safe option.

Furthermore, the source of information is not often a health provider or school, but rather family or friends. Our findings support other studies from LMICs that women most often seek information from female family members, and that these relatives, as well as other sources such as teachers in schools, are not able to provide accurate information [ 21 ].

Better education to both men and women, perhaps through standard approaches of school, but also utilizing times when women are already at health clinics, such as for ANC, could help improve understanding.

The current school curriculum taught in Kenya introduces basic human reproduction or sexuality related content in upper primary levels and secondary education detailed reproductive health education is covered. This relates to knowledge on sexuality and high rates of pregnancy among early education drop outs compared to those with secondary and higher education.

More detailed information may be needed in both primary and secondary schools on these topics. The first ANC visit, since LMP should already be discussed, may be a missed opportunity to educate women about why providers ask about, and the importance of, gestational age.

The time of delivery, family planning or any other postpartum visits which should occur but rarely do could also provide opportunities to provide women more detailed information about their fertile window and menstruation more generally.

However, much information already needs to be covered at all of these health care visits, potentially limiting these visits as viable information exchange opportunities.

Fear of poor person-centered interactions with health care providers, or past negative experiences, appear to be contributing to late ANC attendance, and can impact future health care utilization, again highlighting the need to consider other avenues for education.

Community level health workers and facilities and social networks are currently the dominant source of information, so finding mechanisms to improve knowledge among the nodes of social influence is key. Previous studies have called for strengthening community health workers, however, there is little evidence as to the efficacy of this approach [ 21 ].

Our findings add to the existing literature on stigma around menstruation, which previously was collected only from adolescent girls—this is clearly an issue that spans age and sex. Thus, approaches to provide support to women must include both options of privacy as well as opportunities to engage their partners if desirable.

Periods last around 2 to 7 days, and women lose about 20 to 90ml about 1 to 5 tablespoons of blood in a period. Some women bleed more heavily than this, but help is available if heavy periods are a problem. Ovulation is the release of an egg from the ovaries.

A woman is born with all her eggs. Once she starts her periods, 1 egg develops and is released during each menstrual cycle.

Pregnancy happens if a man's sperm meet and fertilise the egg. Sperm can survive in the fallopian tubes for up to 7 days after sex. Occasionally, more than 1 egg is released during ovulation. If more than 1 egg is fertilised it can lead to a multiple pregnancy, such as twins.

A woman can't get pregnant if ovulation doesn't occur. Some methods of hormonal contraception — such as the combined pill , the contraceptive patch and the contraceptive injection — work by stopping ovulation.

Theoretically, there's only a short time when women can get pregnant, and that is the time around ovulation. It's difficult to pinpoint exactly when ovulation happens but in most women, it happens around 10 to 16 days before the next period.

Women who have a regular, day cycle are likely to be fertile around day 14 of their menstrual cycle, but this won't apply to women whose cycles are shorter or longer.

Find out more about fertility awareness natural family planning.

The Sympto app provides feedback to their users based on their observations, indicating when they are potentially fertile, very fertile or infertile. The key differences between these two apps are i the algorithmic- S vs. user- K interpretation of observations, ii the per-cycle S vs.

per-user K definition of fertility goals users wish to achieve, iii the criteria for the onset of a new cycle, i. self-assessed or automatic, based on first day of reported bleeding K , and iv the resolution at which users can report their observations Table 2 , Supplementary Material.

Given that these are self-tracked data, missing data is a frequent issue, and many cycles within the datasets provided by the app were not suitable for the analyses of this study. We followed an iterative approach in which we first inspected the raw datasets and identified patterns or behavior that were inconsistent with the aims of the study for example, on-going cycles.

Finally, the HMM was used to estimate ovulation and, for the reports of cycle length, follicular and luteal phase durations, only cycles in which ovulation could reliably be estimated were kept Fig.

Sympto: 39, cycles; Kindara: , cycles denote cycles of regular users of the apps in which FAM body signs have been logged. Typically, cycles with long tracking gaps or in which only the period flow was logged were excluded. S defined as ovulatory cycles by the STM algorithm of Sympto, i.

K cycle length was at least 4 days longer than the total number of days in which bleeding was reported. Detected temperature shift was at least 0.

The uncertainty on the ovulation estimation as provided by the HMM framework developed here was lower than ±1. For each standard cycle, the tracking frequency was computed as the number of days with observations in that cycle divided by the length of the cycle.

For both app, observations of all standard cycles were summarized by cycle-day. For the temperature, as the important feature to detect if ovulation has occurred is the relative rise in temperature, a reference temperature was computed for each cycle.

This reference temperature was identified as the 0. Relative temperature measurements were then computed as the difference between the logged temperature and this reference temperature. The distribution at a resolution of 0. The FAM body-signs are considered to reflect the hormonal changes orchestrating the menstrual cycles.

The study was focused on understanding the extent to which these tracked cycles were consistent with previously described menstrual cycle physiologic changes, and the extent to which it was thus possible for app users to estimate timing of ovulation.

Hidden Markov Models HMM are one of the most suitable mathematical frameworks to estimate ovulation timing, due to their ability to uncover, from observations, latent phenomenon, which in this use include the cascade of hormonal events across the menstrual cycle.

HMM have also been previously used for analysis of menstrual periodicity. The HMM as implemented in this study describes a discretization in 10 states of the successive hormonal events throughout an ovulatory menstrual cycle. The HMM definition includes the probabilities of observing the different FAM reported body signs in each state emission probabilities and the probabilities of switching from one state to another transition probabilities.

Emission probabilities were chosen to reflect observations previously made in studies that tested for ovulation with LH tests or ultrasounds, 6 , 8 , 27 while transition probabilities were chosen in a quasi-uniform manner Supplementary Material. The ovulation estimations were robust to changes in transition probabilities but not to variations in emission probabilities Supplementary Fig.

Once the model was defined, the Viterbi and the Backward—Forward algorithms 47 were used to calculate the most probable state sequence for each cycle Supplementary Material and thus to estimate ovulation timing, i.

Finally, a confidence score was defined to account for missing observations and variation in temperature taking time in a window of ~5 days around the estimated ovulation day Supplementary Material.

The ten states, defined as a discretization of the hormonal evolution across the cycle further details in Supplementary Material , are:. Further information on research design is available in the Nature Research Reporting Summary linked to this article.

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Acta Neurol. Rabiner, L. A tutorial on hidden Markov models and selected applications in speech recognition. IEEE 77 , — Download references. The authors are deeply grateful to all Kindara and Sympto users whose data have been used for this study and to the Symptotherm foundation and Kindara company.

In particular, we thank Dr. Wettstein, C. Bourgeois, V. Salonna, T. Newcomer, T. Baras, C. Allémann, P. Ducoeurjoly, and F. Goddyn for sharing their experience, references and for fruitful discussions. We thank S. Holmes, C. Droin and G. Lazzari for discussion on the mathematical modeling.

Department of Surgery, Stanford School of Medicine, Stanford University, Pasteur Dr. Digital Epidemiology Lab, Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne EPFL , Campus Biotech, Chemin des mines 9, , Geneva, Switzerland.

Quality of Life Technologies lab, Institute of Services Science, Center for Informatics, University of Geneva, CUI Battelle bat A, Route de Drize 7, , Carouge, Switzerland. DIKU, University of Copenhagen, Copenhagen, Denmark.

HH, Stanford, CA, , USA. You can also search for this author in PubMed Google Scholar. initiated and conceived the study, analyzed the data and designed the figures, L.

and M. wrote the manuscript. All authors discussed the results and implications and commented on the manuscript at all stages.

Correspondence to Laura Symul. discloses that she is a consultant and medical advisor to Clue by Biowink. The remaining authors declare no competing interests. Open Access This article is licensed under a Creative Commons Attribution 4.

Reprints and permissions. Symul, L. Assessment of menstrual health status and evolution through mobile apps for fertility awareness. npj Digit. Download citation. Received : 15 September Accepted : 08 May Published : 16 July Anyone you share the following link with will be able to read this content:.

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Skip to main content Thank you for visiting nature. nature npj digital medicine articles article. Download PDF. Subjects Computational models Epidemiology Reproductive signs and symptoms. Abstract For most women of reproductive age, assessing menstrual health and fertility typically involves regular visits to a gynecologist or another clinician.

Introduction A broad diversity of fertility awareness methods FAMs has been developed in the past century, 1 , 2 primarily designed to help couples manage fertility and family planning. Full size image. Table 1 Number of observations, cycles and users Full size table. Reported fertility awareness body signs exhibit temporal patterns at the user population level Confident that users regularly logged observations Fig.

Methods Extended Materials and methods can be found in the Supplementary Materials. Mobile phone applications and data acquisition Two de-identified retrospective datasets were acquired from the Symptotherm foundation www.

During a normal cycle, it is the fall of progesterone that brings upon bleeding. If a follicle does not mature and ovulate, progesterone is never released and the lining of the uterus continues to build in response to estrogen. Eventually, the lining gets so thick that it becomes unstable and like a tower of blocks, eventually falls and bleeding occurs.

This bleeding can be unpredictable, and oftentimes very heavy and lasting a prolonged period of time. There are many causes of oligo-ovulation, the medical term used to describe when ovaries do not grow a dominant follicle and release a mature egg on a regular basis.

Polycystic ovarian syndrome PCOS , the most common cause for oligo-ovulation, is a syndrome resulted from being born with too many eggs.

This can result in an imbalance in the sex hormones, and failure to grow a dominant follicle and unpredictable or absent ovulation. Days: More than 7 days Ovulation Indicator: It is possible that there is a hormonal problem resulting in a delay in follicular growth or a structural problem in the uterus making the lining unstable.

What Do Longer Cycles Tell Your Doctor? Prolonged bleeding tells your doctor that the ovary is not responding to the brain signals to grow a lead follicle. This can be a sign of a delayed or absent ovulation. Alternatively, there may be something disrupting the lining of the uterus.

What Causes Long Periods of Bleeding? There are many causes of prolonged bleeding. If follicular growth is not occurring regularly, then prolonged and irregular bleeding can occur. Intermenstrual bleeding or prolonged bleeding may be caused by structural problem like polyps, fibroids , cancer or infection within the uterus or cervix.

In these situations, should an embryo enter the uterus, implantation can be compromised resulting in lower pregnancy rates or an increased chance of a miscarriage. Although rare, a problem with blood clotting can also cause prolonged bleeding and this requires evaluation and care by a specialist.

Days: Rarely or Never Ovulation Indicator: Ovulation may not be occurring What does a Lack of Menstruation tell your Doctor? Either ovulation is not occurring or there is something blocking menstrual blood flow. The patient will have difficultly conceiving naturally without intervention. What Causes Cycles to Stop Occurring?

When a woman does not have a period, this can be caused by a failure to ovulate. Hypothalamic amenorrhea is a potential cause, as well as any of the hormonal imbalances that can cause irregular cycles can also stop the cycles completely.

It is common in women who are considered underweight by the body mass index BMI standards to stop having a cycle. The body requires a certain level of body fat for reproduction and menstrual cycles to occur, and many women who are able to gain weight will see the return of their cycle.

Weight is not the only cause to consider. There are several other causes that should be evaluated as well. If a woman has never had menstrual bleeding, there may have been a problem with the normal development of the uterus or the vagina.

If a woman had menstrual cycles previously, but then stopped, this could be due to a problem with the uterus itself, like scar tissue inside the cavity, or may be due to premature menopause.

If the uterus has not formed or if menopause has occurred, pregnancy is not possible. If the absence of menses is due to scar tissue inside the uterus, then this scar tissue will need to be removed as it can interfere with implantation. If you do not have a normal monthly menses, no matter the amount of time you have been trying to conceive, you should be evaluated by a specialist.

Irregular or absent ovulation makes conception very difficult without intervention. Any woman less than 35 years of age with normal cycles who has not gotten pregnant after a year of trying should see an infertility specialist. If you are 35 or older with a normal menstrual cycle and have been trying for 6 months without success, you should seek care as well.

Normal menstruation indicates that you are ovulating; however, there are other reasons why you may not be able to get pregnant, and these should also be evaluated. For more information about your menstrual cycle or to schedule an appointment with one of our physicians, please speak with one of our New Patient Liaisons at or fill out this brief form.

Medical contribution by Isaac E. Schedule Appointment. Search Search Resources. More on This Topic. Article The relationship between thyroid and infertility.

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So I was forced to ask her. She explained to me and told me I had attained that age and so every month I would have my periods and in case I missed my periods any month it would mean I had become pregnant. Maria, 28, married woman, 2 children.

Women also mentioned talking with other women about menstruation, and its link to fertility, most frequently co-wives or sisters. I normally ask her co-wife because she gets pregnant frequently hence make her have many children.

I do ask her why she gets pregnant like almost immediately after delivery. And she tells me that immediately after delivery she gets her monthly period. I talk to her about such kinds of things and I tell her that after giving birth to my baby who is 8 years now, I stayed 4 years without getting my monthly periods Mona, 25, married woman, 3 children.

Women who felt that they had not received information blamed lack of close female friends or relatives, for example, in the quote below where a woman lived with her grandmother and therefore did not have information until she learned about it in school.

The problem is that I grew up with my grandmother and she never told me anything about menstruation. At times a girl could soil her dress then I would ask to know what happened. But the school contributed a lot in teaching me about menstruation. Akoth, 23, Married woman, 3 children.

A few men discussed how they learned about menstruation from their wives. A few described how, since they had been married at such a young age, they were already married when their wives first experienced menses and they told their husbands about it, so they learned of it then too.

Other men mentioned male friends and elders as key sources of information. I asked one of my friends if women experience menses and he told me that women must experience menses. Every month a woman must experience menses and a woman who is not experiencing menses could be having a problem, you need to take her for treatment.

I then asked him that what problem could be there. John, 25, married man, 1 child. One man discussed in detail the information that he had received in school, which was actually misinformation about the relationship between menstruation and pregnancy. R: In school we were being taught during a subject called health science.

We were told that when a woman is on her menses, a few days to end the menstrual cycle if she engages in sexual intercourse with a man then she can get pregnant… When she is about to clear her menses. I: You were taught in health science that if a woman finished her menses immediately after that if she engages in sex then she can get pregnant?

R: We usually talk, in fact even when this one began and went on for one week, I told him my period had gone on for a whole week in the previous month and this month I had not got my period. He told me to just wait. R: No, he lives far. We meet once in a while. But when I first started having my period he knew the dates; if I told him he would know.

After delivery I hear your cycle can change. R: He would tell me when I know my period is close I should not visit him [laughter] because anything can happen. Another potential source of information about menstruation, especially the link between fertility and menstruation could have been at health facilities, or even at the time of antenatal care visits ANC or delivery.

However, in our study while most women were asked about their LMP during their first ANC visit, they received no other related information, even why they were being asked that question. Younger women were more likely to go to their first ANC visit later in pregnancy, and they cited denial about being pregnant, fear of being scolded by staff or being attended to by male staff, and a general belief that people looked down upon them if they went to the health facility too early, as reasons not to go.

The reason why I feared to go for ANC when I was expecting my baby, is that there were male staff at the facility. I was imagining that I was going to find the same male staff there, so it was making me more worried.

When I was expecting baby in , I just remembered the male staff and it was not easy for me. But when I came I found there were some changes …The male staff were not there, there were sisters, and they were sisters that you can even share with them your ideas.

Auma, 21, married woman, 2 children. I went to the clinic later when the pregnancy was 5 months…. I was afraid because I was going to a certain clinic in Kibera and they were very harsh…The clinic staff, they wanted the exact date when one conceived, which I did not know. And that is what made me fear.

That is what made me take long I went after 3 months then stayed much longer before going back. Awino, 24, married woman, 2 children. Although most respondents knew there was a relationship between menstruation and pregnancy, accuracy of information was very poor. A few respondents did generally have the correct information, however, they were a little unsure and hesitant about the exact details.

As one woman explained:. There are some days after your menses that you cannot get pregnant, they are called safe days something of the sort. Achieng, 31, married woman, 1 child.

Most respondents believed women could become pregnant during menstruation or in the few days before and after. She always tells me when she is experiencing menstrual cycle.

Ojwang, 25, married man, 1 child. Another man explained that he also believed women could become pregnant the few days before her menstruation, as well as during and after. R: To get pregnant for a mother in that menstrual period, with my understanding it is before seeing that blood and after seeing that blood before seven days.

R: It is that before the mother sees that blood, the blood will come and by that time it is still not bleeding and maybe you are having sex and it will find when that egg is mature and in that pregnancy maybe an outcome.

Sometimes the woman has experienced periods and has completed the periods, but before seven days after ending the periods, she can also conceive at that time.

Odhiambo, 26, married man, 2 children. Interestingly, men and women acknowledged some confusion about the relationship between the timing of menstruation and when a woman could get pregnant, discussing how they had heard different information from various sources. Some men are the ones who do say that if a woman is experiencing her menses that is the time he needs to have sex with her to make her pregnant and some are saying that when she is on her menses she is dirty, such that he cannot have sex with the woman.

Women also expressed fear and stigma about their menses, especially fear that it would occur while they were at school or other public settings. When we were going to school some girls could have blood stains at the back of their dresses and that used to worry me a lot.

There was a time when I had gone to visit my Aunt and it happened to me. I: You have said that whenever a girls dress would be stained at the back it would cause you a lot of worries. R: It was worrying because at times it could happen when you are in class and the boys would make fun of it so I used to imagine that the same thing would happen to me.

Mona, 25, married woman, 3 children. Many women tried to track their menstruation, primarily calendars. Some men and women both said that they memorized the date. Some women specifically asked their partners to help them remember the date. Additionally, many women struggled with irregular periods and some stated that they did not know the date of their last menstrual period LMP when they became pregnant, highlighting the need for support for women in tracking their periods.

R: Safe days I think being a woman they know how to calculate this, they know the time they are safe. R: It is important if you are free with your wife talking to her, both of you are free with each other and she can tell you anything on her body and you can also tell her anything on your body, but I think it is important for one to know.

When you know time she is experiencing her menses, then you have sex and she get pregnant and you know that date she has gotten pregnant, you know there are women who are not even aware when they get pregnant and the pregnancy will come as a surprise to her until she is told by other women that are you pregnant and she will say that I am not pregnant.

One woman discussed that her husband thought she was using her period as an excuse and made her show him the evidence blood before believing her.

Women were interested in simple tools to track menstruation, and highlighted a need for privacy. Many women were interested in simple tools like a journal or calendar on paper that they could mark in, with some noting that illiterate women could potentially use that.

Some women already used their phones, by setting an alarm although other women felt that an alarm was a potential breach of privacy. Some had concerns of a phone because could easily be lost or stolen or that someone else could see phone, including children, who were seen as more technology savvy.

You know our kids nowadays they have become active especially on phones because they would want to know almost everything and they would want to know everything on the phone. Otieno, 35, married man, 5 children. Other respondents saw the benefit of a phone since it was something they already had and were using, and that it had the potential to provide other types of health related information as well.

A few respondents even gave suggestions about how a phone could be used to help women, as described below. Yes when you hear that alarm ringing in the phone and you see the picture of a moon indicating, it will act like a message, when you open that message you get all the information that you should be prepared like this, this is what the menstruation period says, you should act like this, you should be clean, pads it tells you like that.

Oguda, 26, married man, 2 children. Overall, however, due to privacy concerns and lack of comfort, most female respondents felt that something like a calendar that they could mark more privately and more easily hide would be more beneficial to them.

Additionally, few respondents had smart phones, and therefore even if there was a mobile option, it would have to be very simple. Notably, a few of the adolescent mothers worried that their parents would be suspicious of something unusual on their mobile phones, and therefore felt that it was not a safe option.

Furthermore, the source of information is not often a health provider or school, but rather family or friends. Our findings support other studies from LMICs that women most often seek information from female family members, and that these relatives, as well as other sources such as teachers in schools, are not able to provide accurate information [ 21 ].

Better education to both men and women, perhaps through standard approaches of school, but also utilizing times when women are already at health clinics, such as for ANC, could help improve understanding.

The current school curriculum taught in Kenya introduces basic human reproduction or sexuality related content in upper primary levels and secondary education detailed reproductive health education is covered.

This relates to knowledge on sexuality and high rates of pregnancy among early education drop outs compared to those with secondary and higher education. More detailed information may be needed in both primary and secondary schools on these topics.

The first ANC visit, since LMP should already be discussed, may be a missed opportunity to educate women about why providers ask about, and the importance of, gestational age.

The time of delivery, family planning or any other postpartum visits which should occur but rarely do could also provide opportunities to provide women more detailed information about their fertile window and menstruation more generally.

However, much information already needs to be covered at all of these health care visits, potentially limiting these visits as viable information exchange opportunities. Fear of poor person-centered interactions with health care providers, or past negative experiences, appear to be contributing to late ANC attendance, and can impact future health care utilization, again highlighting the need to consider other avenues for education.

Community level health workers and facilities and social networks are currently the dominant source of information, so finding mechanisms to improve knowledge among the nodes of social influence is key.

Previous studies have called for strengthening community health workers, however, there is little evidence as to the efficacy of this approach [ 21 ]. Our findings add to the existing literature on stigma around menstruation, which previously was collected only from adolescent girls—this is clearly an issue that spans age and sex.

Thus, approaches to provide support to women must include both options of privacy as well as opportunities to engage their partners if desirable. Addressing stigma and gender norms early on with younger generations could help improve the situation for couples in the future.

It is essential to challenge the pervasive wave of excitement about mobile technology to ensure that such approaches are appropriate for women today for the specific health need. Perhaps in the future, as gender norms and stigma around these issues fades, there will be an even greater opportunity to provide support to women through mobile technology.

Lower tech options also have great potential to be socially acceptable, easily adapted, and cheaply and widely disseminated and scaled up. Lower tech options should not be neglected as we think about how to best provide information and support to a diversity of women today.

That being said, tools such as mobile phones for helping women and potentially their partners track menstruation are of interest to people in this setting. Fears about privacy still persist, and the phone overall feels like a more vulnerable method to most respondents. This highlights the need for personal codes or other carefully designed tools that will ensure privacy.

Despite the potential for mobile phones to provide this resource, in this population and for this topic, careful consideration must be given to design. As with all research, there are limitations to these findings.

Data were collected only from one ethnic group in one region of Kenya, and therefore may not be representative of views and experiences of men and women in other communities in other parts Kenya, especially urban areas, or to remote parts of the country. Additionally, all respondents already had children, so they may have had higher knowledge or lower than respondents who did not.

Also, all respondents had a preterm birth, so might be different, and likely more at risk of having low information about menstruation, than other respondents.

Finally, we did not capture the perspectives of male adolescents, who may have more interest in smart phone technology and also differing levels of knowledge than older males or adolescent women.

Simple tools, both mobile and not, to help women track menstruation, capitalizing on health care contacts and addressing norms and knowledge through social networks have potential for improving knowledge and practices about menstruation and fertility. In our study setting in rural Western Kenya, the smartest option might be very low-tech, and must take into account both technology itself but also comfort with that technology by the population of interest.

Empowering women and men in rural setting with accurate information could help reduce unplanned pregnancies and aid in identifying preterm births, as well as providing women with awareness and knowledge about their bodies and health, aside from pregnancy and childbirth.

The authors would like to acknowledge the generous support of the Preterm Birth Initiative at the University of California, San Francisco, funded through the Bill and Melinda Gates Foundation.

We would also like to thank Nicole Santos and the rest of the Preterm Birth Initiative team at UCSF for their support. Finally, we would like to thank the participants of the interviews for their time and sharing their experiences.

Browse Subject Areas? Click through the PLOS taxonomy to find articles in your field. Article Authors Metrics Comments Media Coverage Peer Review Reader Comments Figures. Abstract An understanding of menstruation and its relationship to fertility can help women know the gestational age of any pregnancies, and thus identify preterm births.

Introduction Understanding the relationship between menstruation and fertility is essential for helping women and their partners plan pregnancies and avoid unintended pregnancies [ 1 , 2 ]. Methods and materials This qualitative study was carried out in among the communities around the shores of Lake Victoria in Bondo, Siaya County, Western Kenya.

Results Demographics The study involved adolescent mothers, mothers aged 20—49 and fathers all who had children below 5 years. Download: PPT. Sources of information about menstruation Respondents received most of their information through school, non governmental organizations NGOs , family or friends.

As is clear in the quote from the following woman, confusion mixed with underlying shame made it hard to reach out to friends for information and support: I would want to hide it from her my friend because I feel embarrassed.

Maria, 28, married woman, 2 children Women also mentioned talking with other women about menstruation, and its link to fertility, most frequently co-wives or sisters.

I talk to her about such kinds of things and I tell her that after giving birth to my baby who is 8 years now, I stayed 4 years without getting my monthly periods Mona, 25, married woman, 3 children Women who felt that they had not received information blamed lack of close female friends or relatives, for example, in the quote below where a woman lived with her grandmother and therefore did not have information until she learned about it in school.

Akoth, 23, Married woman, 3 children A few men discussed how they learned about menstruation from their wives. John, 25, married man, 1 child One man discussed in detail the information that he had received in school, which was actually misinformation about the relationship between menstruation and pregnancy.

I: When she is about to clear her menses? R: I mean if she clears today and tomorrow if she has sex then she can get pregnant I: You were taught in health science that if a woman finished her menses immediately after that if she engages in sex then she can get pregnant?

I: Do you talk to him boyfriend about your monthly period? He told me to just wait I: You told me you use a calendar. Does your boyfriend help you track your period? After delivery I hear your cycle can change I: So how would he react when you would tell him about your menses before you delivered?

R: He would tell me when I know my period is close I should not visit him [laughter] because anything can happen I: What did he mean by that? R: We can get a baby Sharon, Adolescent mother, age 18 Another potential source of information about menstruation, especially the link between fertility and menstruation could have been at health facilities, or even at the time of antenatal care visits ANC or delivery.

Auma, 21, married woman, 2 children I went to the clinic later when the pregnancy was 5 months…. Knowledge about the relationship between menstruation and pregnancy Although most respondents knew there was a relationship between menstruation and pregnancy, accuracy of information was very poor.

Achieng, 31, married woman, 1 child Most respondents believed women could become pregnant during menstruation or in the few days before and after. Ojwang, 25, married man, 1 child Another man explained that he also believed women could become pregnant the few days before her menstruation, as well as during and after.

I: Can you come again? Odhiambo, 26, married man, 2 children Interestingly, men and women acknowledged some confusion about the relationship between the timing of menstruation and when a woman could get pregnant, discussing how they had heard different information from various sources.

Ojwang, 25, married man, 1 child Women also expressed fear and stigma about their menses, especially fear that it would occur while they were at school or other public settings.

R: Yes. I: What was making you get so worried? Tracking of menstruation and support Many women tried to track their menstruation, primarily calendars. I: How were you using safe days? I: So it is the woman who was calculating not you?

R: It is the woman, I: So she was telling you this time no, this time it is okay to have sex? I: Why do you think it is important? I: How can you not move out anyhow? R: Yes I will be waiting for my wife.

I: What happens if you have sex with another woman? R: She may then not give birth. Obwogo, 25, married man, 1 child Women were interested in simple tools to track menstruation, and highlighted a need for privacy.

Otieno, 35, married man, 5 children Other respondents saw the benefit of a phone since it was something they already had and were using, and that it had the potential to provide other types of health related information as well.

Oguda, 26, married man, 2 children Overall, however, due to privacy concerns and lack of comfort, most female respondents felt that something like a calendar that they could mark more privately and more easily hide would be more beneficial to them.

a Modeling framework for the estimation of ovulation timing. Arrows indicate possible state-transition; arrow thickness is not representative of actual transition probabilities Methods. Bottom Examples of menstrual state estimation for the 2rd and 3rd cycle of 2 users.

Top of each chart Original user observations as in Fig. Middle of each chart Colored squares HMM-labeled line represent the most likely sequence of HMM states given the observations Methods.

Bottom of each chart Normalized probabilities of each state on each day of the cycle Methods. b Top Cycle length and estimated ovulation day. Bottom Luteal phase duration, computed as the number of days between the ovulation day excluded and the 1st day of the next cycle excluded.

Vertical lines indicate median values. c Average estimated state probabilities by cycle-day counting from estimated ovulation aggregated by total cycle length in bins of 3 units for all cycles with reliable ovulation estimation.

These estimations allowed the comparison, for cycles with reliable ovulation estimation , cycles, Methods , of the cycle length distribution to those of estimated day of ovulation and of the duration of the luteal phase i.

Cycle length distribution is asymmetrical around the typical 27 to 28 days, with a heavy tail on longer cycles. Similarly, the distribution of the follicular i. Luteal phase duration distribution, which is also asymmetrical, presents however a skew for smaller values and a smaller standard deviation Fig.

Median values were 12 K and 13 S days, which is in line with a previous study that used fertility monitors 31 but shorter than values reported in studies that used luteinizing hormone LH peak for timing of ovulation 14 days. Overall, the comparison with previous studies of the cycle phases duration and range shows that the follicular phase and the whole cycle length have higher mean values and larger ranges than what was previously observed, while the luteal phase duration and range was closer to those found in previous studies 28 , 29 , 31 , 32 , 33 Supplementary Fig.

The primary aim was to provide health practitioners with an overview of how and what FAM app users voluntarily track on these apps. Many, if not most clinicians are unfamiliar with the specifics of health-related apps, and thus the information from this study may provide clinically helpful information.

The secondary aim was to propose a mathematical framework to estimate the underlying hormonal states and most likely day of ovulation from FAM observation.

This allowed a comparison of the duration of the menstrual cycle phases from the present digital study with reported values from previous clinical studies. The typical FAM app user is about 30 years old, lives in a western country in Europe or Northern America and has a healthy BMI.

The height, weight and BMI ranges reported by Sympto users are similar to those reported for the French population, 34 which is where most Sympto users are located.

Thus, to the extent that these users differ from the general population, our results may be more or less generalizable to other populations. The tracking frequency of users that utilize the apps for FAM tracking, is on average higher than the minimum required to detect changes associated with ovulation.

In particular, if users rely on the app for their family planning, i. The reported FAM observations BBT, cervical mucus changes, cervix openness, etc.

are overall aligned with expected patterns of FAM-related body signs, showing that these apps enable hundreds of thousands of users across Europe and North America to follow their fertility and ovulation patterns. Temperature is found to increase by 0.

The aggregated patterns of the reported menstrual body-signs are in good agreement between the two applications despite different app design, user experience and targeted populations Methods. Individual cycles often present noisy profiles, and missing data are a frequent concern.

To partly alleviate these issues, the mathematical framework HMM used in this study discretizes the menstrual cycle in independent successive biologically-relevant states and allows the estimation of ovulation timing along with uncertainty indicators.

The variation range in the ovulation time and in the luteal phase duration was found to be larger than previously described in other studies 29 , 31 , 32 , 35 that relied on much smaller populations but that used biomarkers which offer a greater precision for the estimation of ovulation time.

Interestingly, the cycle phases distributions were slightly different when considering the data from the two apps. These differences might be due to biases found in the user population, especially for users seeking pregnancy that could be at higher risk of sub-fertility if assumed that they start tracking after they have already tried to get pregnant for several months Supplementary Fig.

The strength of this study lies in the scale and precision of the datasets, as a variety of fertility patterns are captured, and as users track the evolution of their cycles at a high frequency over long intervals of time.

It also provides a non-proprietary and replicable mathematical method to infer biological states, and in particular to estimate the timing of ovulation, from fertility awareness self-tracked data. The most obvious potential limitation of this study comes from the origin of these retrospective data: a self-selected possibly biased population, limited medical and general information on users, irregular observation patterns and little control on assessing the validity of the observations, in particular with regard to cervical mucus tracking.

While the tracking frequency limitation can be alleviated through strict selection of users and cycles Methods , all other limiting factors might have introduced biases in the present analysis.

Prospective studies on selected cohorts with appropriate follow-up and information provided to users will provide higher quality data, which could then be used for comparison.

While this study does not assess the benefits for users to use tracking apps compared to relying on their memory or charting their cycles on paper or in their personal calendars, it provides clinicians and digital epidemiologists with an overview of the expected tracking behaviors and body-signs patterns, so that they can evaluate the suitability and benefits of digital self-tracking for their clinical practice or for the design of prospective studies.

Based on the current findings, it appears that digital self-tracking of FAM-related body signs could provide a more accessible, although less precise, means to evaluate the status and evolution of menstrual health than traditional medical monitoring which requires frequent office visits for ultrasounds or hormonal testing from blood or disposable urinary tests.

The self-tracked observations presented here require only a standard thermometer with a 0. Digital self-tracking, compared to paper-based tracking or memory-relying surveys, supplies standardized records and scalable collection methods.

Typically, digital self-tracking of fertility-awareness body signs offers an interesting option for clinicians or researchers interested in changes of a variable of interest for example level of pain or occurrence of a given symptom across the menstrual cycle, or in the overall changes in menstrual rhythmicity.

For investigations requiring a precise assessment of hormonal levels or ovulation timing, additional tests would be necessary until the accuracy and precision of methods using FAM digital records can be established.

The long term and yet very precise recordings presented in this study support the idea that the menstrual cycle, like other biological rhythms, is a vital sign whose variations inform about overall health status. Models could also be established to investigate potential sub-fertility causes anovulation, recurrent early pregnancy losses, etc.

More generally, such data and tracking apps, combined with tracking of other coexisting symptoms, health indicators or behavioral markers, enable the exploration of the menstrual dimension of the course of chronic diseases.

Many menstrual symptoms associated with the pre-menstrual syndrome PMS , such as mastalgia breast pain , or disease, like migraine that can exist in a menstrual or non-menstrual form, have been shown to be associated with steroid hormones although the exact causes have not been elucidated yet.

distinct forms of symptom expression in the population. It is likely that users of such applications already have an increased awareness of their cycles, and this study suggests that these digitally self-tracked observations potentially present an opportunity to facilitate the dialog between patients and their clinicians, helping them to make informed decisions based on quantified indicators.

Extended Materials and methods can be found in the Supplementary Materials. To briefly summarize the methodology used in this study: datasets were first filtered to keep cycles of users using the apps for fertility awareness purposes, i.

to self-identify their fertility window, for at least 4 cycles. Data were then aggregated to describe the overall observation patterns. Finally, a Hidden Markov Model HMM was defined and used to detect ovulation time and assess the reliability of this estimation.

Two de-identified retrospective datasets were acquired from the Symptotherm foundation www. org ; Switzerland and Kindara www.

com ; US upon receiving ethical approval from the Canton Geneva ethical commission CCER Genève, Switzerland , study number — These two apps were selected as they both ranked high in a study comparing the performances of apps marketed to avoid pregnancy using FAMs, 11 as their privacy policies specified the use of their de-identified datasets for research purposes and as their user pools were very large or diverse geographically and culturally.

Sympto was released in and is available worldwide in eight languages English, French, German, Italian, Spanish, Polish, Russian, and Bulgarian. Kindara has been released in and is available worldwide in English.

Both organizations de-identified their datasets before transferring them to the authors. Both apps are available on iOS and Android platforms and are available as free simplified or paid apps.

All features used in this study are available in the free versions of the apps. Kindara provided a random subset of their overall pool of users with at least 4 logged cycles users, 2,, cycles while Sympto provided observations from their long-term users at least 4 cycles tracked with the app and from users who provided their weight, height and menarche age 13, users, 79, cycles.

Both apps offer similar FAM tracking options but differ in their design and user experience Supplementary Fig. A description of the datasets fields is provided in Table 2. Kindara K is primarily marketed to women who wish to achieve pregnancy and does not provide feedback to users in terms of the opening or closing of their fertile window.

Sympto S is marketed as a family planning tool that can be utilized to plan or avoid a pregnancy. The Sympto app provides feedback to their users based on their observations, indicating when they are potentially fertile, very fertile or infertile. The key differences between these two apps are i the algorithmic- S vs.

user- K interpretation of observations, ii the per-cycle S vs. per-user K definition of fertility goals users wish to achieve, iii the criteria for the onset of a new cycle, i. self-assessed or automatic, based on first day of reported bleeding K , and iv the resolution at which users can report their observations Table 2 , Supplementary Material.

Given that these are self-tracked data, missing data is a frequent issue, and many cycles within the datasets provided by the app were not suitable for the analyses of this study.

We followed an iterative approach in which we first inspected the raw datasets and identified patterns or behavior that were inconsistent with the aims of the study for example, on-going cycles. Finally, the HMM was used to estimate ovulation and, for the reports of cycle length, follicular and luteal phase durations, only cycles in which ovulation could reliably be estimated were kept Fig.

Sympto: 39, cycles; Kindara: , cycles denote cycles of regular users of the apps in which FAM body signs have been logged.

Typically, cycles with long tracking gaps or in which only the period flow was logged were excluded. S defined as ovulatory cycles by the STM algorithm of Sympto, i. K cycle length was at least 4 days longer than the total number of days in which bleeding was reported.

Detected temperature shift was at least 0. The uncertainty on the ovulation estimation as provided by the HMM framework developed here was lower than ±1. For each standard cycle, the tracking frequency was computed as the number of days with observations in that cycle divided by the length of the cycle.

For both app, observations of all standard cycles were summarized by cycle-day. For the temperature, as the important feature to detect if ovulation has occurred is the relative rise in temperature, a reference temperature was computed for each cycle.

This reference temperature was identified as the 0. Relative temperature measurements were then computed as the difference between the logged temperature and this reference temperature. The distribution at a resolution of 0. The FAM body-signs are considered to reflect the hormonal changes orchestrating the menstrual cycles.

The study was focused on understanding the extent to which these tracked cycles were consistent with previously described menstrual cycle physiologic changes, and the extent to which it was thus possible for app users to estimate timing of ovulation.

Hidden Markov Models HMM are one of the most suitable mathematical frameworks to estimate ovulation timing, due to their ability to uncover, from observations, latent phenomenon, which in this use include the cascade of hormonal events across the menstrual cycle.

HMM have also been previously used for analysis of menstrual periodicity. The HMM as implemented in this study describes a discretization in 10 states of the successive hormonal events throughout an ovulatory menstrual cycle.

The HMM definition includes the probabilities of observing the different FAM reported body signs in each state emission probabilities and the probabilities of switching from one state to another transition probabilities.

Emission probabilities were chosen to reflect observations previously made in studies that tested for ovulation with LH tests or ultrasounds, 6 , 8 , 27 while transition probabilities were chosen in a quasi-uniform manner Supplementary Material. The ovulation estimations were robust to changes in transition probabilities but not to variations in emission probabilities Supplementary Fig.

Once the model was defined, the Viterbi and the Backward—Forward algorithms 47 were used to calculate the most probable state sequence for each cycle Supplementary Material and thus to estimate ovulation timing, i.

Finally, a confidence score was defined to account for missing observations and variation in temperature taking time in a window of ~5 days around the estimated ovulation day Supplementary Material. The ten states, defined as a discretization of the hormonal evolution across the cycle further details in Supplementary Material , are:.

Further information on research design is available in the Nature Research Reporting Summary linked to this article. Data are however available from the authors upon reasonable request and with permission of Sympto and Kindara. Lamprecht, V.

Natural family planning effectiveness: evaluating published reports. Article CAS PubMed Google Scholar. Peragallo Urrutia, R. et al. Effectiveness of fertility awareness-based methods for pregnancy prevention.

Google Scholar. Marshall, J. Cervical mucus and basal body temperature method of regulating births field trial. Lancet , — Article Google Scholar. Moghissi, K. Prediction and detection of ovulation. In: Modern Trends in Infertility and Conception Control eds Wallach, E. Cyclic changes of cervical mucus in normal and progestin-treated women.

Billings, E. Symptoms and hormonal changes accompanying ovulation. Wilcox, A. BMJ , — Article CAS PubMed PubMed Central Google Scholar. Frank-Herrmann, P. Determination of the fertile window: reproductive competence of women—European cycle databases.

Article PubMed Google Scholar. Bigelow, J. Mucus observations in the fertile window: a better predictor of conception than timing of intercourse. Duane, M. The performance of fertility awareness-based method apps marketed to avoid pregnancy. These disorders may or may not indicate an underlying condition related to infertility or difficulty getting pregnant.

A fertility doctor can be helpful in determining this. Abnormal ovulation is often the underlying cause of irregular periods. Hormones regulate the menstrual cycle and ovulation.

While menstrual disorders can be caused by alterations in hormone levels, these disorders can also sometimes disrupt the hormonal balance, further affecting the menstrual cycle.

Amenorrhea is the absence of a menstrual period. This can be a temporary or permanent lack of menstruation. Missing one period is generally not cause for concern, and missing a period can also be an indication of pregnancy.

But missing more than one period in the absence of pregnancy may be a sign of an underlying disorder that can cause infertility. Amenorrhea caused by a structural, genetic, or hormonal condition that prevents menstruation from beginning in puberty is called primary amenorrhea.

Conditions that can result in primary amenorrhea include gonadal dysgenesis, Turner syndrome, PCOS, androgen insensitivity, and congenital adrenal hyperplasia. Amenorrhea occurring after a woman starts having periods is called secondary amenorrhea.

It is most often caused by conditions that affect the uterus or the organs involved in hormone production including the ovaries, hypothalamus, and pituitary gland. Causes of secondary amenorrhea include:. Oligomenorrhea is the medical term for when a woman has infrequent periods and regularly goes more than 35 days without menstruating.

This menstrual disorder is most often due to a side effect of hormonal birth control. It can also be caused by thyroid problems, diabetes, eating disorders, high levels of physical activity in younger women, and increased prolactin in blood that can be caused by medications.

But oligomenorrhea can sometimes indicate the presence of PCOS, which can cause infertility. For these reasons, it is best for a woman who regularly goes more than 35 days without a period to seek medical evaluation.

It is often marked by the loss of so much blood and cramping that the woman cannot go about her normal activities. Women should seek medical care if their bleeding soaks one or more tampons per hour over more than two hours.

Other symptoms that may indicate that treatment is needed include needing to change sanitary protection during the night, bleeding for more than a week, presence of large blood clots, and signs of anemia such as fatigue and shortness of breath.

Please I just find out my period cycle is now 26 days instead of normal hope am saved? My period is every 26 days and lasts for 3 days what are my chances of getting pregnant.

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