ovulation test strips
Reading time 5 mins.

What Your Period Can Tell You About Your Fertility

If you’re looking for signs of high fertility as a woman, your monthly period can be full of indicators. The length, volume, and presence (or lack of) ovulation can give you an indication of how fertile you are. Read on to learn how to start to determine your level of fertility at home—with and without ovulation test strips.
Written by Bird&Be

In this article /

    ovulation test strips
    Before you start actively trying to conceive, it can be hard to know much about your fertility and your chances of getting pregnant—but your period, and your overall menstrual cycle—can provide some insight. Cycle length, period length, flow details, and ovulation can all provide context and indicate whether to seek out support with your fertility.  
    Frequent changes in your period, for example, can be signs of low fertility, because your cycle can be easily affected by our sleep, stress, nutrition and supplementation. When looking into your fertility, it’s worth taking stock of your lifestyle, including sleep, stress, and nutrition, and looking into potential supplementation. And never hesitate to investigate your periods with a doctor. 

    A little background on your cycle. It can be broken into three parts:
    • the follicular phase (the first day of your period to ovulation),
    • ovulation,
    • and the luteal phase (from after ovulation to the day before your next period).
    Each phase is dependent on rising and falling hormones and the processes they put into motion, kick-starting the next phase. Which means when one thing is off, it can affect the whole cycle.  

    Here’s what to know about your period and menstrual cycle when it comes to signs of fertility.

    Cycle length

    The average menstrual cycle is 28 days, but anywhere from 22 to 34 is considered “normal”. Having too short or too long of a cycle could be an indication that something is off—including unbalanced hormones, poor egg quality, low ovarian reserve, or high stress. To measure cycle length, count from the first full day of bleeding until the day before your next period begins. Not everyone has a cycle that runs like clockwork, so keeping track month after month can help establish what is “normal” for you.  

    If your cycle is short

    A short cycle is considered 21 days or less and can be attributed to anovulation (when ovulation isn’t occurring), perimenopause (ovarian aging), diminished ovarian reserve (you don’t have that many eggs left) or high follicular estrogen levels (resulting in early-in-the-cycle ovulation). While short cycles should be investigated, it’s especially good to check in with a doctor if your cycles are suddenly short after being in the normal range.
    If your cycle is long

    A long cycle is considered 35 days or longer, and often means that ovulation is delayed or hasn’t happened. In general, long cycles are linked to low progesterone, which can be a sign of poor egg quality or poor hormone function, leading to anovulation. A long cycle can also indicate PCOS, having either excessive or low body fat, insulin resistance or can be affected by lifestyle factors like abnormal sleep, smoking or overexercising. 

    Period flow

    The length of your period and the volume of your flow can also provide some insight into your fertility. For example, a long flow is considered more than seven days of bleeding and many of the reasons why you might have one are the same as heavy flow.

    If you have light or absent flows

    While it might seem like a perk to have a light or absent flow (AKA hypomenorrhea), it can be an indicator of low hormone levels. Your hormones contribute to creating a thick uterine lining, readying it for implantation. When implantation doesn’t happen, you shed the lining (your period), but if there wasn’t much lining, there won’t be much to shed. Other culprits contributing to light or absent flows include poor egg quality, high stress, Asherman’s syndrome (scarring in the uterus), and extreme body fat or weight loss.
    Note on hormonal birth control: Once taking a hormonal birth control pill, you no longer experience a traditional bleed, instead it’s a “withdrawal” bleed. It happens when the level of hormones in your pills drop off and usually is slightly lighter or different than your pre-BCP periods.

    If you have heavy or long flows

    A heavy flow (AKA menorrhagia) can be a huge pain—and should always be flagged with your doctor because it can lead to iron deficiency. Almost a quarter of heavy flow cases can be attributed to a clotting or bleeding disorder, but it can also be due to uterine fibroids or polyps, ovulatory dysfunction (including PCOS), or endometriosis (when the tissue that lines the uterus grows into the walls of the uterus).

    Note on IUDs: While hormonal IUDs can cause a lighter period, the non-hormonal copper IUD can lead to heavier bleeding and more cramping.

    Normal menstrual loss is about 30 to 40 millilitres per cycle—menorrhagia is a volume greater than 80mL. The easiest way to measure your flow is to monitor how full your menstrual cup is before emptying it by using the visible measurement lines on the side of the DIVA Cup.

    How to Track Ovulation

    Ovulation is a prerequisite for getting pregnant on your own. One of the best ways to understand your likelihood of conceiving is to confirm that you are, in fact, ovulating.  
    The only surefire way to confirm ovulation is with your doctor/ob gyn, but the most reliable way to track it at home is with LH strip tests.  
    These at-home tests look a lot like pregnancy tests, but they track luteinizing hormone (LH) levels instead of the pregnancy hormone (hCG). LH surges right before ovulation (it triggers the release of an egg), so if you see an LH surge on your test, ovulation should occur within the next 24 to 36 hours.  
    Ovulation typically happens about two weeks before your next period, so it’s best to start testing on cycle day eight or nine (if you have a normal 28-day cycle) to confirm. You may need to test a few days (or even multiple times a day) to see a positive result.

    Bird&Be’s Ovulation Tests are ultra-sensitive and 99.9% effective at picking up that LH surge. There are nine in a box, so you can test over the course of a few days; sometimes the LH surge happens so quickly that you can miss it unless you test a few times.

    bird&be ovulation test strips
    If you don’t see a positive LH test, or you see several days in a row of positive tests, it’s worth going to a doctor for more investigation. No LH surge likely means no ovulation, whereas a sustained surge makes it harder to track your fertile window at home.

    Other signs and symptoms of ovulation if you’re tracking at home, including charting cervical mucus and basal body temperate (BBT).
    Whether you have regular or irregular cycles, tracking your cycle for your peak fertility days is the best way to conceive on your own. Seek the support of a fertility specialist for the necessary test results and support for your reproductive health to increase your chances if you’re experiencing any of the irregularities above.


    About the contributor

    A Canadian company offering fertility-supporting products and services to help you do just that, without leaving your home and no matter what stage of the journey you're in. The future of fertility is home.


    • Byams, Vanessa R, et al. “Evaluation of Bleeding Disorders in Women with Menorrhagia: A Survey of Obstetrician-Gynecologists.” American Journal of Obstetrics and Gynecology, vol. 207, no. 4, 1 Oct. 2012, pp. 269.e1–269.e5, www.ncbi.nlm.nih.gov/pmc/articles/PMC4410699/, https://doi.org/10.1016/j.ajog.2012.07.010. Accessed 8 Nov. 2023.
    • Mumford, Sunni L., et al. “The Utility of Menstrual Cycle Length as an Indicator of Cumulative Hormonal Exposure.” The Journal of Clinical Endocrinology & Metabolism, vol. 97, no. 10, Oct. 2012, pp. E1871–E1879, https://doi.org/10.1210/jc.2012-1350.
    • Gudmundsdottir, Brynja R, et al. “Quantification of Menstrual Flow by Weighing Protective Pads in Women with Normal, Decreased or Increased Menstruation.” Acta Obstetricia et Gynecologica Scandinavica, vol. 88, no. 3, 1 Mar. 2009, pp. 275–279, https://doi.org/10.1080/00016340802673162. Accessed 8 Nov. 2023.
    • Planned Parenthood. “What Are the Side Effects of IUDs?” Www.plannedparenthood.org, www.plannedparenthood.org/learn/birth-control/iud/iud-side-effects.