Fertility and Perimenopause: AMH, Egg Quality & Your Cycle

Fertility and perimenopause are often treated as completely separate stages of a woman’s life. One conversation is about getting pregnant. The other usually doesn’t begin until periods start changing, symptoms appear, and menopause suddenly feels much closer.

But the same ovaries, eggs, hormones, and brain-ovary communication are involved in both.

That connection was the focus of two recent episodes of unPAUSED, where Dr. Mary Claire Haver, a board-certified OB-GYN, certified menopause practitioner, and adjunct professor of obstetrics and gynecology at the University of Texas Medical Branch, sat down with Dr. Natalie Crawford, a double board-certified OB-GYN and reproductive endocrinologist and author of The Fertility Formula. (Listen here and here.)

Together, they explored a part of women’s health that is rarely explained this way: changes in ovarian function affect fertility during the reproductive years and can also help women understand some of the changes that occur as they approach perimenopause.

“The fertility story and the menopause story are the same story,” says Dr. Haver.

That does not mean a fertility test can tell you exactly when perimenopause will begin. Reproductive aging happens over time. Egg quantity changes. Egg quality changes. Hormone signaling changes. Menstrual cycles may change too. Understanding those changes can give women better information about their bodies, whether they are trying to get pregnant, trying not to get pregnant, or wondering what a changing cycle might mean.

What You Need to Know

• Fertility and perimenopause are connected through ovarian aging. Changes in ovarian function affect egg quantity, egg quality, ovulation, hormone production, and menstrual cycles.

• Your menstrual cycle can provide useful information. A persistent change in cycle length, bleeding, or ovulation patterns is worth paying attention to.

• AMH (Anti-Müllerian Hormone) provides information about ovarian reserve. It is much better at estimating egg quantity (ovarian reserve) than egg quality and cannot tell you whether you will become pregnant naturally. 

• Low AMH does not mean pregnancy is impossible. It should be interpreted alongside age, menstrual history, medical history, and reproductive goals.

• Age 35 is not a fertility cliff. Fertility changes gradually, with age-related changes in egg quality becoming increasingly important.

• Male fertility matters too. Male factors contribute to a substantial share of infertility cases and should be evaluated when applicable.

• Pregnancy is still possible during perimenopause. Ovulation becomes less predictable, but it can still occur.

• Reproductive health matters beyond pregnancy. Menstrual, fertility, and pregnancy history belong in a woman’s lifelong health record.

Are Fertility and Perimenopause Actually Connected?

Yes. Fertility and perimenopause are connected through changes in ovarian function that occur throughout a woman’s reproductive life. These changes affect ovulation, menstrual cycles, hormone production, egg quantity, and egg quality.

The ovaries do not suddenly become relevant when a woman wants a baby, then disappear from the health conversation until menopause. Ovarian function is changing across the reproductive years.

Dr. Haver describes this connection plainly: “What happens to your ovarian function in your 30s and 40s does not stay in your 30s and 40s. It shapes your perimenopause, your metabolic health, your brain, and your bones.”

Research has also found associations between infertility and later health outcomes, including cardiovascular and bone health. These associations do not mean infertility causes heart disease or osteoporosis. They suggest that reproductive health may sometimes provide information about underlying health conditions or shared risk factors.

PMOS (formerly called PCOS), endometriosis, thyroid disorders, metabolic conditions, and diminished ovarian reserve can affect fertility. Some of these conditions also remain relevant to health later in life.

Dr. Crawford describes fertility as a health marker, but she is careful about what that means. “Does infertility cause any of those? Absolutely not,” she says.

The goal is not to make women afraid of what infertility might mean for their future. It is to stop treating reproductive information as disposable once pregnancy is no longer the goal.

Key takeaway: Fertility and perimenopause are connected by ovarian and reproductive aging, but fertility problems do not determine a woman’s future health.

Why Is My Menstrual Cycle Getting Shorter in My 30s or 40s?

Menstrual cycles can become shorter as reproductive aging changes the timing of follicle development and ovulation. A persistent change from your normal cycle pattern can provide useful information, but shorter cycles alone do not diagnose perimenopause.

To understand why, it helps to know what is happening during a menstrual cycle.

During the first part of the cycle, called the follicular phase, follicle-stimulating hormone (FSH) helps a group of follicles in the ovaries develop. One typically becomes dominant and contains the egg that may eventually be released.

That developing follicle produces estrogen. When the hormonal signals reach the appropriate point, luteinizing hormone (LH) surges and triggers ovulation.

After ovulation comes the luteal phase. The follicle that released the egg becomes the corpus luteum and produces progesterone, helping prepare the uterine lining for a possible pregnancy.

“The brain talks to the ovary, the ovary grows an egg and makes hormones,” Dr. Crawford explains. “Those hormones talk back to the brain, but also talk to the uterus and prepare it.”

As ovarian reserve declines with age, this communication begins to change. FSH may rise and follicles can begin developing earlier in the cycle, which can shorten the follicular phase and sometimes the overall cycle.

If a woman has consistently had a 28-day cycle and begins having 26-, 25-, or 24-day cycles, the change is worth noticing. What matters is not simply whether a cycle fits inside a textbook definition of “normal.” A meaningful change from a woman’s established pattern can provide information too.

Your Menstrual Cycle Is a Vital Sign

Many women reach their 30s and 40s without ever being taught how to understand their menstrual cycle beyond knowing when their period is expected.

That is a missed opportunity.

Cycle length, bleeding patterns, ovulation, cervical mucus, and other changes can provide information about reproductive function. Fertility awareness is useful even when pregnancy is not the goal.

Tracking can start with the basics:

• Record the first day of each period.

• Track the number of days between periods.

• Notice persistent changes in cycle length.

• Pay attention to changes in flow.

• Note spotting or bleeding between periods.

• Track new or worsening pelvic pain.

• If relevant to your goals, learn how ovulation signs such as cervical mucus or basal body temperature work.

Apps and wearable devices can make tracking easier, but predictions are still estimates. A device cannot know with certainty that ovulation occurred simply because an algorithm predicted it.

Which Period Changes Should You Talk to Your Doctor About?

Perimenopause can change bleeding patterns, but new symptoms should not automatically be blamed on hormones.

Very heavy bleeding, bleeding between periods, bleeding after sex, significant new pelvic pain, or pain during intercourse should be evaluated. Fibroids, adenomyosis, endometriosis, polyps, thyroid disorders, ovulatory dysfunction, medications, and other conditions can affect menstrual bleeding.

Key takeaway: Your cycle is useful health information. Pay attention to changes from your normal pattern, not only whether an app labels your cycle “normal.”

What Does an AMH Test Tell You About Your Ovarian Reserve?

AMH, or antimüllerian hormone, is one marker clinicians use to estimate ovarian reserve, which refers primarily to the number of eggs remaining. It does not directly measure egg quality and cannot tell a woman whether she will become pregnant naturally.

AMH is produced by cells surrounding developing ovarian follicles. Dr. Crawford uses the image of a vault to make the concept easier to understand.

The ovaries contain a reserve of eggs. Over time, groups of follicles are recruited from that reserve and begin developing. AMH gives clinicians information about this pool of developing follicles.

“It’s not telling us that you are fertile,” Dr. Crawford says. “It’s not telling us you will have any problem getting pregnant or that you won’t.”

AMH can be particularly useful during fertility treatment because it helps reproductive endocrinologists estimate how the ovaries may respond to medications used to stimulate follicle development.

What AMH cannot do is function as a yes-or-no fertility test.

Can You Get Pregnant With Low AMH?

Yes. A woman can become pregnant with low AMH. A low result suggests lower ovarian reserve, but it does not mean that ovulation or natural conception is impossible.

AMH cannot tell whether the egg released during a particular cycle will have the correct number of chromosomes. It cannot determine whether sperm will fertilize that egg or whether an embryo will implant.

This is why a low AMH result should never be interpreted as “you cannot get pregnant.”

It can still be meaningful information, particularly when combined with age, menstrual history, family-building goals, and other clinical findings.

Does AMH Measure Egg Quality?

No. AMH is primarily a marker of egg quantity, not egg quality. There is currently no routine clinical test that can directly measure the quality of all the eggs remaining in a woman’s ovaries.

Age remains one of the most useful clinical predictors of egg quality because the likelihood of chromosome errors increases as eggs age.

Can AMH Predict When Perimenopause or Menopause Will Start?

Not with enough precision to predict an individual woman’s menopause timeline from a single AMH result. Researchers have found relationships between AMH levels and the timing of menopause across groups of women, but that is different from accurately predicting one woman’s age at menopause.

Current professional guidance does not recommend using a single AMH measurement to predict an individual woman’s age at menopause.

Dr. Crawford takes a more proactive position on women having access to ovarian reserve information, provided they understand what the test can and cannot tell them.

“I strongly believe that as a physician, my job is not to be the gatekeeper of you getting data about your body,” she says.

That distinction matters. AMH should not be presented as a countdown clock, but a well-explained result may still prompt a useful conversation about family planning, fertility preservation, ovarian reserve, or whether evaluation by a reproductive endocrinologist makes sense.

Key takeaway: AMH provides information about ovarian reserve. It is not an egg-quality test, a fertility score, or an exact prediction of when menopause will occur.

Egg Quantity vs. Egg Quality: What’s the Difference?

Egg quantity and egg quality are related to reproductive aging, but they describe two different things.

Understanding this difference helps correct one of the biggest misconceptions about the biological clock. Fertility is not simply a matter of counting down the eggs until none remain.

Does Turning 35 Mean You’re Running Out of Eggs?

No. There is no biological switch that flips on a woman’s 35th birthday. Fertility declines over time, and age-related changes in egg quality are an important part of that decline.

“Most women think that there’s this magic cliff at age 35,” says Dr. Crawford. Many assume this is because women suddenly begin running out of eggs, but she points out that “the majority of women are nowhere close to out of eggs at age 35.”

Women are born with their lifetime supply of eggs, so egg quantity does decrease with age. The quality of those eggs changes too.

Why Does Egg Quality Decline With Age?

An egg has been inside a woman’s body since before she was born. Its chromosomes must remain organized for years before the egg matures and completes the steps required for ovulation and potential fertilization.

Dr. Crawford compares those chromosomes to kindergartners standing in carefully organized lines. The longer they have to remain perfectly arranged, the greater the chance someone ends up out of line.

With age, the cellular machinery responsible for separating chromosomes becomes more prone to errors. An egg or embryo can then have an abnormal number of chromosomes, known as aneuploidy.

This is one reason fertility declines and miscarriage risk rises with maternal age.

“It does get harder because of this egg quality, genetic normalcy, and egg competency,” Dr. Crawford says.

Age 35 still has clinical significance. Fertility evaluation is generally recommended sooner for women 35 and older, and some pregnancy risks increase with age. That is different from treating 35 as an expiration date.

Key takeaway: Fertility does not fall off a cliff at 35. Reproductive aging is gradual, and changes in egg quality are an important part of the story.

How Does Chronic Inflammation Affect Fertility and Ovarian Health?

Chronic inflammatory states may affect processes involved in reproduction, including ovarian function, hormone signaling, and the environment surrounding developing eggs. Inflammation is not a single explanation for infertility, and claims that reducing inflammation will guarantee pregnancy go far beyond the evidence.

Inflammation itself is not inherently harmful. The immune system uses inflammatory responses to fight infection and heal injury, and controlled inflammatory activity is involved in normal reproductive processes.

Persistent chronic inflammation is different.

Dr. Crawford uses a walkie-talkie analogy to explain the communication required for reproductive function. The brain sends signals to the ovaries, and ovarian hormones send signals back.

“If inflammation is static interference on the radio, the brain can’t hear whatever signal the ovary’s trying to send,” she says.

It is an analogy, not a literal description of what happens inside the body. It helps illustrate an important point: fertility depends on communication among several systems, including reproductive, metabolic, and immune pathways.

Infertility can also involve age, genetics, PCOS, endometriosis, ovulatory disorders, uterine or tubal conditions, sperm factors, and other medical conditions. Women should be cautious of anyone promising that a particular diet, supplement, or “anti-inflammatory” protocol will fix fertility.

Key takeaway: Chronic inflammation may be one factor affecting reproductive health, but infertility rarely has one universal cause. Check your daily inflammation score with The ‘Pause Life’s Inflammation Quiz.   

When Should You Get a Fertility Evaluation?

Women younger than 35 are generally advised to seek an infertility evaluation after 12 months of regular unprotected intercourse without pregnancy. For women 35 and older, evaluation is generally recommended after six months. Women over 40 may benefit from more immediate evaluation.

Those timelines do not mean every woman should wait.

Earlier evaluation may be appropriate when there are irregular menstrual cycles, cycles shorter than 25 days, known or suspected endometriosis, uterine or tubal disease, sexual dysfunction, a history of treatments that may affect ovarian function, or concern about male infertility.

Dr. Crawford questions the idea that women should always have to demonstrate infertility before anyone investigates possible problems.

“It does not make sense to say, ‘I’m not even gonna do testing on you until you’ve failed, and then we’ll do the testing,’” she says.

The goal is not to order every available fertility test for every woman. Testing should answer a useful clinical question, and results should be explained carefully.

Key takeaway: The standard six- or 12-month timelines do not apply to every situation. Known risk factors or concerning cycle changes may justify an earlier conversation.

How Much Does Male Fertility Matter?

Male factors contribute to a substantial share of infertility cases, so fertility evaluation should include the male partner when applicable. Testing only the woman can miss an important part of the picture.

Dr. Crawford describes infertility this way: “One-third is only a female factor, one-third is only a male factor, and one-third has combined factors.”

A male fertility evaluation may include reproductive and medical history, medication and substance use, and semen analysis.

There is also an important biological difference between eggs and sperm. Women are born with their lifetime supply of eggs. Men continuously produce new sperm.

“Sperm is constantly made every single day,” Dr. Crawford explains.

That makes the health and exposures of the male partner before conception relevant too.

Can Cannabis Affect Male Fertility?

Research has raised concerns about cannabis use and male reproductive health, though the evidence is still developing.

One prospective cohort study found an association between male marijuana use at least once per week before conception and a higher risk of spontaneous abortion compared with no male marijuana use. Because the study was observational, it cannot prove cannabis caused the pregnancy losses.

Research has separately found associations between sperm DNA fragmentation and recurrent pregnancy loss.

The practical advice is straightforward: men who are trying to conceive should discuss cannabis, tobacco, medications, supplements, and other exposures with their clinician rather than assuming fertility preparation is solely the woman’s responsibility.

Key takeaway: Male fertility should be considered from the beginning, not after every possible female factor has been investigated.

What Is “Trimester Zero”?

“Trimester Zero” refers to the months before conception, when women and men can address health conditions, medications, and habits that may affect reproductive and pregnancy health.

Dr. Crawford frames it with a practical question: “What can we do before we get pregnant, the three months beforehand?”

Preconception care can include:

• Reviewing medications and supplements with a clinician

• Taking folic acid as recommended

• Managing diabetes, thyroid disease, high blood pressure, and other medical conditions

• Reviewing vaccination status

• Avoiding smoking and recreational drugs

• Getting regular physical activity

• Eating a nutrient-dense dietary pattern

• Addressing sleep and mental health

• Discussing previous pregnancy complications or losses

• Evaluating irregular menstrual cycles

• Addressing possible male fertility factors

Sperm development takes roughly two to three months, which makes the health of the male partner during this period relevant too.

This is not a prescription for a perfect pregnancy. Healthy habits cannot guarantee conception, prevent every miscarriage, or overcome every cause of infertility.

Dr. Haver and Dr. Crawford have each experienced pregnancy loss themselves. Their experiences reinforce an important point for patients: reproductive outcomes should never be reduced to whether a woman ate perfectly, exercised enough, managed her stress, or took the right supplements.

Key takeaway: Preconception health belongs to both partners, and no lifestyle routine can guarantee fertility or a healthy pregnancy.

Can You Get Pregnant During Perimenopause?

Yes. Pregnancy remains possible during perimenopause because ovulation can still occur. Ovulation may become less predictable, but irregular ovulation is not the same thing as no ovulation.

This is especially important for women who assume changing or skipped periods mean contraception is no longer necessary.

Pregnancy and perimenopause can also share symptoms. A missed or unusual period, breast tenderness, fatigue, sleep changes, and mood changes can occur with either.

If pregnancy is possible and a period is late or unusual, taking a pregnancy test is a reasonable first step. Women who do not want to become pregnant still need appropriate contraception until menopause has been reached.

Key takeaway: Perimenopause does not mean pregnancy is impossible. Ovulation can continue even when cycles become irregular.

What Should You Discuss With Your Healthcare Clinician?

Understanding the connection between fertility and perimenopause does not mean every woman needs hormone testing or a fertility workup. It means knowing which changes deserve a closer look.

Consider talking with your healthcare clinician if:

• Your menstrual cycles have become consistently shorter, longer, or less predictable.

• You have very heavy bleeding, bleeding between periods, or bleeding after sex.

• You have new or severe pelvic pain.

• You are concerned about future fertility or ovarian reserve.

• You are younger than 35 and have been trying to conceive for 12 months.

• You are 35 or older and have been trying for six months.

• You are over 40 and want to become pregnant.

• You have PCOS, endometriosis, thyroid disease, or a history of pelvic surgery.

• You have experienced recurrent pregnancy loss.

• You have received chemotherapy or pelvic radiation.

• Early menopause or primary ovarian insufficiency runs in your family.

• There is a known or suspected male fertility concern.

Key Terms to Know

Ovarian reserve: An estimate of the number of eggs remaining in the ovaries.

AMH: Antimüllerian hormone, a hormone used as one marker of ovarian reserve.

Egg quality: The ability of an egg to mature, fertilize, and potentially support normal embryo development, including having the correct number of chromosomes.

Follicular phase: The portion of the menstrual cycle before ovulation, when ovarian follicles develop.

Luteal phase: The portion of the menstrual cycle after ovulation, when the corpus luteum produces progesterone.

Aneuploidy: An abnormal number of chromosomes in a cell, including an egg or embryo.

Perimenopause: The transition leading up to menopause, during which ovarian function and menstrual cycles become less predictable.

Menopause: The point reached after 12 consecutive months without a menstrual period when there is no other medical explanation.

Fertility and Perimenopause Belong in the Same Health Conversation

Women are often taught about fertility only when they want to become pregnant and about perimenopause only when symptoms begin. That leaves an enormous amount of reproductive health education missing in between.

Understanding how the ovaries change over time can help connect those stages. Menstrual cycles can provide useful information. AMH can answer certain questions about ovarian reserve, but not every question about fertility. Egg quantity and egg quality are different. Male fertility belongs in the conversation too.

Dr. Haver and Dr. Crawford each came to this conversation with medical expertise and personal experience with pregnancy loss. Their message is not that women should test everything, track everything, or spend their reproductive years worrying about what comes next.

It is that women deserve accurate information about their bodies.

Knowing more cannot predict every reproductive or health outcome, but it can help women recognize changes, understand what those changes may mean, ask better questions, and make informed decisions with their healthcare team.

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