What You Need to Know Exploring Irregular Periods and Fertility
In this blog post about ovulation, we discussed how irregular, frequent, or widely spaced periods can present challenges when trying to conceive. Let’s explore this issue further and how menstrual irregularities can signal underlying health conditions or impact fertility.
Menstrual bleeding usually occurs about two weeks after ovulation. Regular periods indicate that ovulation is happening predictably, but cycle lengths that fall outside the typical range of 21-35 days could be cause for concern. I would argue that 24 days is the minimum acceptable cycle length—let’s explore why that’s important.
The Problem with Cycles Longer Than 35 Days
When menstrual cycles extend beyond 35 days, they often become less predictable and more erratic, both in frequency and in the amount of blood lost.
This can signal hormonal imbalances related to conditions such as polycystic ovarian syndrome, thyroid disorders, or even the onset of menopause. These complex conditions carry unique risks, and self-diagnosis isn’t advisable. If your periods are regularly more extended than 35 days, Dr Simon Nothman recommends that a thorough evaluation from a healthcare provider is essential.
This holds even if you’re not currently trying to conceive, as these conditions can have wide-ranging health implications beyond fertility. For more information on this, see my blog post on PCOS.
From a fertility standpoint, fewer periods mean fewer chances for ovulation, reducing your opportunity to conceive. For example, if you have periods every 35 days or more, you may only ovulate about ten times a year, as opposed to the average of 12. Women whose cycles are even longer may find it harder to predict ovulation, leading to frustration in timing intercourse for conception. Other fertility factors, like sperm quality, also play a role and could further reduce the likelihood of natural conception, increasing the need for medical assistance.
What About Shorter Menstrual Cycles?
Frequent periods, or cycles shorter than 24 days, can also pose fertility issues. Women with cycles under 24 days are at higher risk of having a low ovarian reserve, putting them at risk of early ovarian failure or premature menopause. This scenario requires medical evaluation, as it can lead to long-term complications and fertility issues.
When a cycle is short, ovulation can happen earlier—sometimes as early as day 7 in a 21-day cycle. This means that while the fertile window might be considered a 6-day period, the peak fertile days are the day of ovulation and the day or two before it. This could cause women to miss their chance for conception, particularly if intercourse during the menstrual period is avoided, which is common in some cultures. Additionally, the shorter time between periods may not give the uterine lining enough time to develop correctly, reducing the chances of successful implantation.
For women at risk of premature ovarian insufficiency, fertility preservation options such as egg freezing should be considered at a relatively young age to maximise their future reproductive choices.
The Impact of Medications on the Menstrual Cycle
It’s important to remember that all of this applies to natural menstrual cycles—not those controlled by medications, such as the contraceptive pill. The pill can mask natural cycle patterns and make it difficult to assess what’s happening with your ovaries. Many women use the pill to manage heavy periods, acne, or irregular bleeding. Still, even if you don’t plan on getting pregnant soon, a fertility review is essential to understand your reproductive health.
Menstrual Quality: What Does It Tell You About Your Health?
While we’ve focused on cycle timing, the quality of your period is also a key indicator of health. Heavy or prolonged periods may signal uterine issues such as fibroids, polyps, or conditions like adenomyosis. Light or brief periods could suggest intrauterine adhesions (Asherman syndrome) or problems with the development of the uterine lining.
Painful periods, too, might point to endometriosis or adenomyosis—conditions that affect fertility and often require medical attention. In any of these cases, seeking early assessment is essential to allow time for intervention if needed.
Next Steps
If your periods are unusually frequent, irregular, or marked by very heavy or light bleeding, consider making an appointment with a fertility specialist. Early diagnosis and treatment can improve your overall reproductive health and increase your chances of a successful pregnancy.
Read our introductory primer on conception and infertility for more information.
FAQs about Irregular Periods and Fertility
Can irregular periods affect my chances of getting pregnant?
Yes, irregular periods can make it harder to predict ovulation, which reduces your chances of conceiving. Irregular cycles may also indicate underlying conditions that impact fertility, such as PCOS or thyroid issues, making predicting ovulation harder and may reflect an underlying problem. Read the blog post on the topic for more information.
What is considered an irregular period?
A period is generally considered irregular if the cycle length varies significantly from month to month or falls outside the typical range of 21 to 35 days.
Can frequent periods be a sign of a fertility issue?
Yes, persistent periods (cycles shorter than 24 days) can indicate lower ovarian reserve or other reproductive health issues. It’s essential to consult a healthcare provider for further evaluation.
When should I see a doctor about irregular periods?
If your periods are consistently irregular, infrequent, or very frequent, it’s advisable to seek medical advice. Conditions such as PCOS, thyroid disorders, or ovarian insufficiency could be contributing factors.
Can birth control affect my menstrual cycle when I stop using it?
Yes, birth control can affect your cycle even after stopping. It may take time for your natural cycle to re-establish itself, which is why it’s essential to review your fertility health with a doctor when planning for pregnancy.
Ready to Address Irregular Periods and Fertility Concerns?
If you’re experiencing irregular periods or have concerns about your fertility, schedule a consultation with Dr Simon Nothman today. Early assessment and intervention can help improve your chances of conceiving and guide you toward a healthy reproductive future.