How to support fertility through cycle tracking and early screening

Podcast episode originally published on September 24, 2025

Fertility support starts long before someone tries to get pregnant. In this episode of the WHOOP Podcast, reproductive endocrinologist and OB-GYN Dr. Natalie Crawford joins Senior Vice President of Research, Algorithms, and Data at WHOOP Emily Capodilupo to explain why menstrual cycle patterns, birth control choices, ovarian reserve, and daily habits can all offer useful clues about hormonal health.

Crawford explains what a regular cycle can and cannot tell you, when painful or heavy periods deserve follow-up, how hormonal contraception changes the signals you can observe, and why earlier screening may give people more options later. For Crawford’s full breakdown of cycle tracking, contraception, and fertility planning, watch Episode 342 of the WHOOP Podcast.

Why does fertility matter even if you are not trying to get pregnant?

Fertility matters early because ovulation and cycle patterns can reveal how well the hormonal system is functioning. Crawford argues that infertility is often a first signal of deeper issues, including insulin resistance and chronic inflammation, that may also shape later cardiometabolic health.

In practical terms, that means menstrual tracking is useful beyond family planning. If you know what is typical for your own cycle, you have a better chance of spotting when the pattern changes. Crawford points out that a person can have a period every month and still have subtle hormonal disruption, especially if the luteal phase shortens or the timing of ovulation shifts. Those early changes are easy to miss when nobody is recording them.

Crawford frames the point directly:

"Your fertility is a sign of your hormonal health, but it’s also a health marker for the future."

For WHOOP members, that kind of tracking becomes more useful when cycle logs and symptoms sit next to Sleep, Recovery, HRV, and resting heart rate inside the WHOOP app. A dated record of patterns gives an OB-GYN or fertility specialist more to work with than memory alone. WHOOP has written more about how members can track reproductive health across life stages.

If you want to hear Crawford connect fertility to long term health risk in her own words, watch the full episode over on Youtube.

What you should take away

• Fertility can act as an early health signal long before pregnancy becomes a goal
• Regular bleeding does not always mean the underlying hormonal pattern is fully healthy
• Cycle tracking is most useful when it establishes your own baseline over several months
• A symptom and cycle record can make a medical visit more specific and more productive

How does hormonal birth control change your natural cycle?

Once fertility is framed as a health signal, the next question is how hormonal birth control changes that signal. Crawford’s answer is clear: hormonal contraception can be an appropriate choice, and it works by changing the normal conversation between the brain, the ovaries, the uterine lining, and the cervix.

She starts with the natural cycle. Follicle stimulating hormone, or FSH, helps recruit a follicle and mature an egg. As that follicle grows, estrogen rises. When estrogen stays high enough for long enough, the brain responds with a luteinizing hormone, or LH, surge, and ovulation happens. After ovulation, the follicle becomes the corpus luteum, which produces progesterone for roughly two weeks unless a pregnancy signal keeps it active.

Crawford uses a specific threshold to explain the trigger for ovulation:

"When estrogen levels are high enough for long enough, so 200 picograms for 50 hours, then the brain knows there’s a mature egg and it will send out a surge of a hormone called LH."

Combined oral contraceptive pills use synthetic estrogen and progestin to interrupt that sequence. The estrogen tells the brain there is already enough hormone activity, so it reduces FSH and LH signaling. The progestin changes cervical mucus and thins the uterine lining, which makes sperm transport and implantation less likely. The bleed on the pill reflects hormone withdrawal created by the medication rather than spontaneous ovulation and a natural luteal phase.

Crawford also separates methods that often get lumped together. A hormonal IUD works more locally at the uterus and cervix, although some people will also stop ovulating for part of the device lifespan. An implant or shot delivers enough progestin to suppress ovulation more consistently. Those differences matter when people are interpreting symptoms or planning for conception.

Her other key point is timing. Crawford says the pill clears quickly, with a roughly 28-hour half-life, so the value of stopping it 3 to 6 months before trying to conceive is observation time, not a cleanse. That window lets you see whether heavy bleeding, delayed ovulation, acne, or long cycles return once the natural pattern reappears. Those returning patterns can uncover PCOS, endometriosis, thyroid issues, or other problems that were present before contraception ever entered the picture.

Crawford spends more time on pill, IUD, implant, and shot physiology in the full episode over on Youtube.

What you should take away

• Hormonal birth control prevents pregnancy by changing brain to ovary signaling and by altering cervical mucus and the uterine lining
• The bleed on a birth control pill does not represent a fully natural menstrual cycle
• Different hormonal contraceptives work through overlapping but distinct pathways
• Stopping the pill a few months before trying to conceive can help reveal your underlying cycle pattern

How can you advocate for the right hormone and fertility workup?

Because hormonal contraception can hide the pattern underneath, the quality of the medical visit becomes the next practical step. Crawford says many people receive a prescription quickly, especially for acne, heavy bleeding, or painful periods, without enough time spent on the question of why those symptoms started.

Her first recommendation is simple: book the right visit type. An annual exam is a preventive visit with a short, checklist-driven format. A problem-focused visit gives your clinician time to hear the full story, consider testing, and discuss what the results might mean.

Crawford makes the timing point bluntly:

"A problem-focused visit is typically 20 to 30 minutes, and an annual’s 12."

The second recommendation is to arrive with specifics. Write down when the symptom started, how it changed, whether it disrupts school, work, exercise, or daily activity, and what happens month to month. Crawford repeatedly warns people not to minimize what they are experiencing. If pain makes you cancel plans or bleeding soaks through products or clothing, say so clearly.

The third recommendation is to leave with next steps that are concrete. Ask what test is being ordered, what the clinician is looking for, how to schedule follow-up imaging or blood work, when results should arrive, and whether the next conversation will happen by portal message, phone call, or another visit. That summary at the end of an appointment can prevent the common situation where someone knows they were evaluated but does not know what to do next.

This part of the episode also matters for people whose first prescription came from another specialty. If a dermatologist started birth control for acne, or another clinician managed symptoms outside gynecology, Crawford advises bringing that history back to an OB-GYN so the reproductive context is part of the plan.

What you should take away

• A problem-focused visit gives more room for symptom review and testing than an annual preventive visit.
• Specific details about timing, severity, and change over time make a better workup more likely.
• Heavy bleeding, severe pain, or irregular cycles deserve the question of why, not only a symptom suppressor.
• A good visit ends with a clear plan for tests, results, and follow-up.

Which period symptoms can point to endometriosis, fibroids, or PCOS?

Once the visit is structured correctly, the next issue is knowing which symptoms deserve a workup. Crawford says four broad patterns should raise concern: severe pain, very heavy bleeding, lots of spotting between periods, and cycle timing that becomes unpredictable or shifts far from your usual pattern.

Endometriosis is the condition she spends the most time unpacking. Crawford describes it as an inflammatory disease in which endometrial-like tissue grows outside the uterus, including around the ovaries, fallopian tubes, bowel, and the lining of the abdomen. Those lesions respond to estrogen, which can drive chronic inflammation and, in more advanced cases, scarring and anatomical changes that interfere with fertility.

She gives the prevalence clearly:

"1 in 10 women have endometriosis. As many as 30 to 50% of women with unexplained infertility have endometriosis as well."

The symptom list matters. Crawford says painful periods that caused missed school or activities as a teenager are especially telling because those memories were formed before years of normalization set in. Gastrointestinal symptoms that worsen around menstruation, including bloating, diarrhea, or constipation, can also fit the picture. So can pain with deeper penetration during intercourse. A normal ultrasound does not rule endometriosis out, because definitive diagnosis still requires surgery, although severe disease can sometimes create changes visible on imaging.

Heavy bleeding pushes the differential in a slightly different direction. Crawford says bleeding through clothes or through menstrual products should trigger an evaluation for fibroids, polyps, bleeding disorders, or other uterine causes. Fibroids are common and often easier to identify because ultrasound can show them directly. The main mistake is assuming that heavy bleeding is simply part of having a period.

Irregular cycles with signs of high androgens raise suspicion for polycystic ovary syndrome, or PCOS. Crawford references the Rotterdam criteria, which define PCOS through two of three findings: irregular or absent periods, clinical or laboratory signs of high androgens, and ultrasound evidence of high follicle count. In real life, that can look like long or erratic cycles, acne, chin or mustache-like hair growth, hair thinning at the temples, central weight gain, fatigue, and a long history of symptoms that were treated cosmetically without addressing the hormonal driver. WHOOP has covered adjacent questions about cycle phase trends in Episode 212 of the WHOOP Podcast on training through all phases of life and in Podcast 265: Women’s Health Listener Qs.

What you should take away

• Severe period pain, heavy bleeding, frequent spotting, and unpredictable cycle length deserve medical follow-up
• Endometriosis can be present even when ultrasound findings are normal
• Bleeding through clothes or menstrual products can point to fibroids, polyps, or bleeding disorders
• Irregular cycles plus acne, excess facial hair, or scalp hair thinning should prompt an evaluation for PCOS

Should you check ovarian reserve before trying to conceive?

Symptom tracking can surface one kind of risk. Ovarian reserve testing asks a different question: how much timing flexibility might you have later. Crawford believes more people should ask that question earlier, even though the American College of Obstetricians and Gynecologists does not recommend routine anti-Müllerian hormone, or AMH, testing for people who are not experiencing infertility.

Crawford’s argument is that ovarian reserve data can change decisions. AMH is a blood test that reflects hormone production from the granulosa cells surrounding small follicles. An antral follicle count, or AFC, is the ultrasound version of the same concept. Both estimate how many eggs are available in the monthly recruitable pool. Neither tells you whether those eggs are chromosomally normal, and neither test measures egg quality directly.

If an AMH result is unexpectedly low in someone in their mid-20s, Crawford says that person may want a fertility consult, different timing, or a discussion about egg freezing. If the test is normal, it does not guarantee future fertility. It only removes one major concern from the list.

Crawford states her view directly:

"I recommend, and I wish all women earlier would get an AMH test in their mid-20s regardless if they want to get pregnant or not get pregnant."

She also adds an important caveat for people on hormonal birth control, during pregnancy, or while breastfeeding. AMH can read lower during times of stronger ovarian suppression. Crawford still thinks the test can be useful because many people will remain in a normal range, but a low result in that setting deserves a more personalized discussion with a fertility specialist rather than panic. The same logic applies to online test ordering. Data can be useful, and interpretation matters.

If you want the full back-and-forth on AMH, AFC, and why Crawford differs from current society guidance, the full episode over on Youtube.

What you should take away

• AMH and antral follicle count estimate ovarian reserve, not egg quality
• A normal AMH result does not guarantee future fertility, and a low result does not answer every fertility question by itself
• Crawford supports earlier AMH testing because it can change planning and referral decisions
• Hormonal birth control, pregnancy, and breastfeeding can suppress AMH and make interpretation more nuanced

What daily habits support hormonal health and fertility over time?

After screening and diagnosis, the area you can still influence most directly comes from daily behavior. Crawford is careful here. She does not claim sleep, stress management, exercise, or nutrition can stop age-related chromosomal change in eggs. She does say these habits can influence inflammation, insulin resistance, and ovulatory stability, which are central parts of the fertility picture she sees in clinic.

Sleep comes first. Crawford says many adults sleep too little and start the day in a more inflammatory state than they realize. Short sleep increases stress hormone load and makes insulin regulation harder, which can worsen the exact physiology that shows up in cycle disruption.

Her sleep target is direct:

"Your body probably needs 7.5 to 8 hours of sleep at minimum."

From there she moves to stress. Cortisol is designed for short bursts of threat, not endless background activation. Crawford recommends finding at least 20 minutes each day that lowers stress in a real way, whether that is walking, yoga, mindfulness, journaling, talking with a friend, or another practice you can repeat. The point is to create a reliable downshift, because chronically elevated stress can suppress the brain signals that help coordinate ovulation.

Movement and strength training help for a related reason. Crawford explains that skeletal muscle gives the body another way to handle glucose demand, which is useful when insulin resistance is part of the problem, as it often is in PCOS. Cardio has value, and she wants people to think beyond cardio alone and deliberately build muscle.

Nutrition rounds out the picture. Crawford ties gut health to estrogen metabolism and inflammatory load. Her priority is more fiber from fruits, vegetables, and other plant foods, fewer ultra-processed foods and added sugars, and a better overall balance of protein sources. She specifically points to plant proteins as being associated with better ovulation patterns and lower inflammatory burden.

This is where WHOOP can be useful in a very concrete way. When period logs sit beside Sleep, Recovery, HRV, resting heart rate, and behavior notes in the WHOOP app, people can see whether worse symptoms tend to arrive after short sleep, high strain, travel, illness, or sustained stress. WHOOP has also explored related topics in a pregnancy exercise and HRV study discussion and in its article on how to support your body through menopause.

Crawford’s closing message on behavior is worth hearing in full, especially if you want her explanation of inflammation, insulin resistance, and what remains within your control. Watch the full episode over on Youtube.

What you should take away

• Sleep is a frontline fertility behavior because chronic sleep loss raises stress load and worsens insulin regulation
• Daily stress reduction works best when it is specific and repeatable, rather than aspirational
• Strength training supports hormonal health partly by increasing skeletal muscle and improving glucose handling
• Higher fiber intake and fewer ultra-processed foods can support gut health, estrogen metabolism, and inflammatory control

The bottom line

• Fertility can surface early signs of hormonal, metabolic, and inflammatory stress long before pregnancy becomes a goal
• Hormonal birth control can be the right choice and can still mask underlying cycle patterns that deserve evaluation
• Severe period pain, bleeding through clothes or products, frequent spotting, and sudden cycle variability are clear reasons to book a dedicated medical visit
• Endometriosis often takes years to diagnose and can affect fertility even when standard ultrasound findings look normal
• PCOS can show up through irregular cycles, acne, excess facial hair, scalp hair thinning, fatigue, and central weight gain
• AMH and antral follicle count estimate ovarian reserve, but neither test measures egg quality or guarantees fertility
• Sleep, stress regulation, strength training, and higher fiber intake can support hormonal health by lowering inflammatory and insulin-resistance pressure

Frequently asked questions about things discussed in this episode

How does WHOOP help you track menstrual cycle changes that matter for fertility?

WHOOP lets you log periods and symptoms in the WHOOP app and view those entries beside Sleep, Recovery, HRV, and resting heart rate trends, which can make repeat patterns easier to discuss with an OB-GYN or fertility specialist.

What does WHOOP show if you use hormonal birth control?

WHOOP still shows sleep, recovery, strain, and symptom trends while you use hormonal birth control, but hormonal contraception can change or mask the natural cycle pattern underneath those observations.

Can WHOOP diagnose endometriosis, PCOS, fibroids, or infertility?

WHOOP does not diagnose endometriosis, PCOS, fibroids, or infertility. WHOOP helps surface repeatable changes in cycle timing, symptoms, sleep, and recovery that can support a more informed clinical visit.

How does WHOOP measure HRV and resting heart rate in this context?

WHOOP measures HRV and resting heart rate during sleep and shows how those values trend over time, which can add context when cycle phase, stress, illness, or recovery demands change.

What does WHOOP do for stress and sleep habits that affect hormonal health?

WHOOP tracks Sleep, Recovery, and daily strain so you can see whether short sleep, heavy training, travel, or sustained stress keep lining up with worse cycle symptoms or slower recovery.

How can WHOOP support conversations with an OB-GYN or fertility specialist?

WHOOP gives you a time-stamped record of cycle logs, symptoms, sleep, and recovery patterns, which can make it easier to describe what changed, when it started, and whether the issue repeats across several months.

When cycle logs sit beside Sleep, Recovery, HRV, and resting heart rate in the WHOOP app, fertility conversations get earlier, more specific, and much easier to act on.