Can PCOS Cause Infertility? Causes, Tests & Treatment (2026)

Can PCOS Cause Infertility? An Evidence-Based Guide to Causes, Diagnosis, Treatment and Pregnancy Outcomes

Yes, polycystic ovary syndrome (PCOS) can reduce fertility, and it is one of the most common causes of anovulatory infertility, meaning infertility caused by ovulation that is infrequent or absent. But PCOS is a condition of reduced and delayed fertility, not absolute infertility. With ovulation induction, many women conceive, and large clinical trials now show clearly which treatments work best.

Three points matter most:

The main fertility problem in PCOS is usually anovulation, not poor egg quality in every cycle.
Letrozole is now the first-line medicine for ovulation induction in the 2023 international guideline, ahead of clomiphene.
PCOS also changes the risk profile of pregnancy itself, so preconception care and antenatal monitoring are part of fertility care, not an afterthought.

A Note on the New Name: PCOS Is Becoming PMOS

In May 2026, following a 14-year global consensus process published in The Lancet, polycystic ovary syndrome was officially renamed polyendocrine metabolic ovarian syndrome (PMOS). The change was made because “polycystic” misleads: the follicles seen on ultrasound are not pathological cysts, and many women with the condition do not have them. The new name stresses that this is a lifelong hormonal and metabolic condition, not only an ovarian or fertility problem.

The transition is planned over about three years, with the new name fully adopted in the 2028 update of the international guideline. The diagnostic criteria have not changed for now. Because most patients still search for “PCOS”, this article uses PCOS and notes the new term where relevant. In South Asia you may also hear “PCOD”; this is an older, less precise term for the same clinical picture.

How Common Is PCOS, and How Much of Infertility Does It Explain?

Estimates of PCOS prevalence among women of reproductive age range from roughly 8% to 13% depending on the diagnostic criteria and the population studied, and a large share of affected women remain undiagnosed. Because ovulation problems are involved in a substantial proportion of female infertility, and PCOS is the leading cause of ovulation problems, PCOS accounts for most cases of anovulatory infertility.

Two cautions keep this in perspective:

PCOS is not the cause of every pregnancy delay in a woman who has it. Tubal disease, endometriosis, uterine factors, age and male-factor infertility (which contributes to about half of infertile couples) can coexist.
Fertility is a spectrum. Women with PCOS who ovulate regularly may conceive without help; those who ovulate rarely may take much longer.

The Biology: Why PCOS Disrupts Ovulation

PCOS is not a single defect. It is better understood as several interacting disturbances that converge on the ovary.

1. The hypothalamic-pituitary signal is altered

Ovulation depends on a coordinated rhythm: the hypothalamus releases GnRH in pulses, the pituitary responds with LH and FSH, and the ovary responds with follicle growth and estrogen. In many women with PCOS, GnRH pulses are faster. Faster pulses favour LH production over FSH. The result is relatively high LH and relatively low FSH, which is the wrong balance for selecting and growing one dominant follicle.

2. Excess androgens

LH stimulates ovarian theca cells to produce androgens. In PCOS the theca cells often produce more androgen than normal, partly because of intrinsic differences in ovarian steroid production and partly because of the stimulation described below. Androgens drive acne, excess hair growth and scalp hair thinning, and they interfere with the final stages of follicle maturation.

3. Insulin resistance and hyperinsulinaemia

Insulin resistance is common in PCOS, including in many women who are lean, though it is more frequent and more severe with higher body weight. When cells respond poorly to insulin, the pancreas produces more of it. High insulin has three relevant effects:

It amplifies LH-driven androgen production in the ovary.
It lowers sex hormone-binding globulin (SHBG) in the liver, so more testosterone circulates in active form.
It may directly disturb follicle development.

This insulin-androgen loop is why metabolic health and fertility are so closely linked in PCOS.

4. Follicle arrest and high AMH

Anti-Müllerian hormone (AMH) is made by small growing follicles. Women with PCOS typically have a larger pool of small antral follicles and therefore higher AMH. Elevated AMH is thought to make follicles less responsive to FSH, which helps explain why many follicles begin to grow but arrest at a small size, around 5 to 8 mm, rather than one maturing and ovulating. This is the origin of the “string of pearls” ultrasound appearance.

This also explains an apparent paradox: a woman with PCOS often has a large number of eggs in reserve, yet cannot reliably release one.

5. Genetic and developmental factors

PCOS runs in families, and twin studies suggest a high heritable component. Genome-wide studies have identified multiple associated regions, including genes involved in FSH and LH signalling and in androgen production, with no single gene responsible. There is also experimental and observational evidence that exposure to excess androgens in early development may contribute in some people, though this is not established as a cause in all women.

6. Effects on the endometrium

Fertility is not only about ovulation. In PCOS the endometrium may show altered hormone responsiveness, including reduced sensitivity to progesterone, and chronic anovulation exposes the lining to estrogen without regular progesterone. This is one reason doctors advise that women who go many months without a period should discuss protecting the endometrium, since long-term unopposed estrogen increases the risk of endometrial hyperplasia.

What the Evidence Says About Egg Quality

A common claim is that PCOS means poor egg quality. The evidence does not support a blanket statement. During IVF, women with PCOS usually yield more eggs, but a higher proportion may be immature, and some studies suggest differences in how eggs mature in culture. Whether this translates into lower embryo quality independent of age and metabolic health is still debated.

What is clear is that age remains a major determinant of egg quality and live-birth chances in women with PCOS, just as in other women. A high AMH or high follicle count should never be read as a guarantee of fertility.

PCOS Phenotypes and Why They Matter for Fertility

The Rotterdam criteria define PCOS when two of three features are present (after other causes are excluded): ovulatory dysfunction, clinical or biochemical hyperandrogenism, and polycystic ovarian morphology. Combining them produces four phenotypes:

Phenotype	Hyperandrogenism	Ovulatory dysfunction	Polycystic ovarian morphology	Typical fertility and metabolic picture
A (classic)	Yes	Yes	Yes	Most likely to be anovulatory; highest metabolic risk
B	Yes	Yes	No	Similar to A in ovulation and metabolic risk
C (ovulatory)	Yes	No	Yes	Often ovulates; fertility problems may be milder
D (non-hyperandrogenic)	No	Yes	Yes	Anovulation present; metabolic risk generally milder

This is why two women with the same diagnosis can have very different fertility. A woman with phenotype C may conceive with minimal intervention, while a woman with phenotype A or B may need ovulation induction. Phenotype also helps predict metabolic risk, which shapes preconception care.

How PCOS Is Diagnosed (2023 International Guideline)

Adults need at least two of three features, with similar conditions excluded:

Irregular cycles and ovulatory dysfunction. Cycles shorter than 21 days or longer than 35 days, or fewer than eight cycles a year, in a woman more than three years past her first period. Regular cycles do not fully exclude ovulatory dysfunction.
Hyperandrogenism, either clinical (hirsutism, acne, scalp hair loss) or biochemical (raised free testosterone, calculated free androgen index, or similar markers). Where available, high-quality assays are preferred because routine testosterone immunoassays can be inaccurate, especially at the lower levels seen in women.
Polycystic ovarian morphology. On ultrasound, this means 20 or more follicles per ovary (measured with an appropriate high-frequency vaginal probe) or an enlarged ovarian volume. The 2023 guideline also allows a reliable AMH measurement to be used in adults as an alternative to ultrasound for this criterion. If a woman already has irregular cycles and hyperandrogenism, no imaging is needed.

Adolescents are handled more cautiously, because irregular cycles and acne are common in normal puberty. Diagnosis requires both irregular cycles (defined by time since first period) and hyperandrogenism. Ultrasound and AMH should not be used for diagnosis in this age group.

Tests that exclude look-alike conditions typically include pregnancy testing, thyroid function (TSH), prolactin, and, where indicated, 17-hydroxyprogesterone to look for non-classic congenital adrenal hyperplasia. Rapid-onset hair growth, voice deepening or very high testosterone should prompt investigation for an androgen-secreting tumour.

Tests that are not useful for diagnosis: the LH to FSH ratio is not a diagnostic criterion and should not be used to confirm or exclude PCOS.

The Metabolic Assessment Every Woman With PCOS Should Have

Because PCOS carries metabolic risk, the guideline recommends assessing more than reproductive hormones. For a woman planning pregnancy this typically includes:

Glucose tolerance. An oral glucose tolerance test is recommended in women with PCOS planning pregnancy or seeking fertility treatment, because HbA1c and fasting glucose alone can miss impaired glucose tolerance.
Blood pressure, lipids and weight trends.
Screening for mood and sleep problems. Depression, anxiety and obstructive sleep apnoea are more frequent in PCOS and can affect health in pregnancy.

Asian and South Asian women develop insulin resistance and type 2 diabetes at lower body weights than white European women, so lower BMI thresholds are used for risk assessment in these groups. A woman with a “normal” BMI can still have significant metabolic risk, and a normal weight does not remove the need for glucose testing.

How to Tell Whether You Are Ovulating

Ovulation tracking in PCOS is less reliable than in women without it.

Urine LH tests can give false positives because LH may be persistently raised.
Basal body temperature charts are unreliable for confirming or timing ovulation.
Mid-luteal progesterone (about seven days before an expected period, or timed to the cycle length) is a reasonable objective check that ovulation occurred.
Ultrasound follicle monitoring can show a dominant follicle growing and rupturing and is the standard during medicated cycles.

A positive home test, a bleed or a normal-looking cycle length each tell only part of the story. A proper fertility assessment and diagnosis, including hormone testing and ovulation assessment, can confirm what is actually happening.

Preconception Care and Lifestyle: What the Evidence Actually Shows

Lifestyle measures are recommended for all women with PCOS, but the evidence deserves careful reading.

Weight loss in women with higher body weight improves ovulation, insulin sensitivity and androgen levels. Even modest loss, in the region of 5 to 10% of body weight, can restore cycles in some women. It is, however, not a prerequisite for treatment in every case, and PCOS also occurs in lean women.
Trial evidence on live birth is mixed. A large randomised trial of lifestyle intervention before fertility treatment in women with obesity (the LIFEstyle study) did not show higher rates of healthy live birth overall, although it did increase spontaneous conception. The practical lesson is that lifestyle change improves health and may help ovulation, but delaying all treatment for long periods can be counterproductive, particularly in women over 35.
Respectful communication matters. The 2023 guideline emphasises weight-neutral communication. Weight stigma is associated with delayed care and worse outcomes, and care should not blame patients.

Other preconception steps include folic acid supplementation (the dose is individualised, and a higher dose may be advised with obesity), reviewing medicines and supplements, stopping smoking, limiting alcohol, treating any thyroid disease, and optimising glucose and blood pressure.

Treatment: Step by Step, With the Strongest Evidence

Step 1: Letrozole is now first-line ovulation induction

For anovulatory women with PCOS and no other infertility factor, the 2023 international guideline recommends letrozole as first-line pharmacological treatment. Letrozole is an aromatase inhibitor, which temporarily reduces estrogen production. This increases FSH release from the pituitary and supports growth of follicles.

The landmark trial. In the PPCOS II trial (Legro et al., New England Journal of Medicine, 2014), 750 women with PCOS were randomised to letrozole or clomiphene for up to five cycles.

Cumulative live birth was 27.5% with letrozole versus 19.1% with clomiphene (rate ratio 1.44).
Ovulation per cycle was also higher with letrozole (61.7% versus 48.3% of treatment cycles).
Twin pregnancy was less frequent (about 3.4% versus 7.4%), and rates of pregnancy loss were similar (about 32% versus 29%).
Hot flushes were more common with clomiphene, while fatigue and dizziness were more common with letrozole.

Why it may work better. Clomiphene blocks estrogen receptors throughout the body, including in the cervix and endometrium, and this antiestrogenic effect can thin the lining and affect cervical mucus even when ovulation occurs. Letrozole does not block receptors, and its short half-life means it is cleared before implantation. Letrozole also tends to produce fewer mature follicles, which lowers multiple-pregnancy risk.

Safety. Early concerns about birth defects arose from a small preliminary report. In PPCOS II, overall congenital anomaly rates did not differ significantly between the two drugs, and the trial authors stated that larger studies were needed to settle the question. Subsequent meta-analyses and the 2023 guideline have not identified an excess risk of malformations. A 2026 systematic review and meta-analysis likewise found letrozole more effective than clomiphene with a lower multiple-pregnancy risk and similar miscarriage risk.

Practical points. In many countries letrozole is used off-label for ovulation induction, because it was originally licensed for breast cancer. It must be prescribed and monitored by a clinician after pregnancy has been excluded. Doses and cycle days should come from your doctor, not from online schedules.

You can explore Kamran Fertility’s fertility treatment options in Lahore, including ovulation induction for PCOS.

Step 2: Alternatives and second-line options

Option	Role	Key evidence and cautions
Clomiphene citrate	Alternative when letrozole is unavailable or unsuitable	Effective, but lower live-birth rates than letrozole in the largest trial; higher twin rate; may thin endometrium
Metformin	Adjunct, mainly where insulin resistance or metabolic concerns exist	Improves ovulation modestly; benefit on live birth alone is uncertain; less effective than letrozole as a sole ovulation-induction agent
Gonadotrophin injections (FSH)	Second-line when oral agents fail	Low-dose, step-up regimens with ultrasound monitoring aim for a single dominant follicle; risks include multiple pregnancy and ovarian hyperstimulation
Laparoscopic ovarian drilling	Selected women who fail oral agents	Can restore ovulation; avoids multiple pregnancy from stimulation, but is surgical, and excess tissue damage may theoretically reduce ovarian reserve
Inositol and other supplements	Not first-line	The 2023 guideline considers evidence limited; discuss with a doctor rather than relying on them alone

Step 3: Intrauterine insemination and IVF

IVF is considered when ovulation induction fails, when another factor such as tubal disease or significant male-factor infertility is present, or when age makes faster treatment sensible. The guideline treats IVF as a third-line option for anovulatory PCOS without other factors.
Ovarian hyperstimulation syndrome (OHSS) is a key risk, because the ovaries of women with PCOS can respond excessively. Strategies that lower the risk include the GnRH antagonist protocol, using a GnRH agonist trigger instead of hCG, and freezing all embryos for a later transfer.
Single embryo transfer is recommended to avoid multiple pregnancy, which carries higher risks for both mother and babies.
In vitro maturation (IVM) of immature eggs is an option in selected cases that further reduces OHSS risk, though availability varies.

You can read more about the differences between IVF and IUI, and when ICSI treatment may be considered. If you are weighing up clinics, see How to Choose the Right IVF Center in Lahore and the guide to IVF treatment cost in Pakistan.

When Treatment Does Not Work

Before escalating treatment, a good clinician will check:

Whether ovulation actually occurred
Whether dose and monitoring were adequate
Whether the tubes and uterine cavity have been assessed
Whether semen analysis has been done

Repeating the same treatment indefinitely without reassessment wastes time, which matters most for women in their mid to late thirties. If you have already had treatment elsewhere, Kamran Fertility also provides second opinions and previous treatment reviews.

When to See a Fertility Specialist

The standard advice for couples without known problems is to seek assessment after 12 months of trying under age 35, and after 6 months at 35 or older, with earlier assessment over 40. Women with PCOS and very infrequent or absent periods already have a probable ovulation problem, so there is no reason to wait a full year.

Seek help promptly if you:

Have had periods stop for several months
Have known tubal or pelvic disease
Have a partner with known semen abnormalities

Not sure where to start? Read about a fertility assessment for both partners, or learn about male fertility testing and what a semen analysis means.

Pregnancy With PCOS: Risks, and What Reduces Them

PCOS does not end with conception. A large 2024 systematic review and meta-analysis in Nature Communications pooled 104 studies and 106,690 pregnancies. It found higher odds of miscarriage, gestational diabetes, gestational hypertension, pre-eclampsia and caesarean section in women with PCOS. Importantly, the increased odds remained significant when women were matched for age and BMI and when only high-quality studies were analysed, which suggests PCOS itself, and not only body weight, contributes to the risk.

Earlier smaller analyses estimated gestational diabetes odds at roughly two to three times higher, and pregnancy-induced hypertension and pre-eclampsia at similarly raised levels, along with a modest increase in preterm birth. The size of the effect varies between studies and depends on diagnostic criteria, age, BMI and how pregnancy was achieved.

Two things are worth stressing:

These are increased risks, not certainties. Most women with PCOS have uncomplicated pregnancies.
The guideline recommends that PCOS status be recorded in all women planning or in early pregnancy, so that blood pressure, weight gain, glucose and fetal growth can be monitored closely. Researchers have noted that awareness of PCOS as a pregnancy risk factor remains low among both patients and professionals.

Practical measures include early glucose screening, healthy weight gain targets, blood pressure checks, and a discussion with your obstetric team about whether preventive treatments are appropriate in your case.

Long-Term Health Beyond Fertility

Because PCOS is a lifelong condition, treating fertility is only one part of care. Women with PCOS have a higher lifetime risk of type 2 diabetes, hypertension, dyslipidaemia, fatty liver disease, sleep apnoea, depression and anxiety, and, if cycles remain very infrequent, endometrial hyperplasia.

Symptoms often change over time, and some women find cycles become more regular in their late thirties and forties. A diagnosis made during a fertility work-up is therefore also an opportunity to plan long-term screening.

Myths Versus Evidence

“PCOS means I can never have a baby.” False. Most women with PCOS who want children can conceive, often with ovulation induction.
“Polycystic ovaries are cysts that need removal.” False. The follicles are normal early follicles; surgery is not routine treatment.
“I have regular periods, so I can’t have PCOS.” Not always. Cycles can be regular even with hyperandrogenism and polycystic morphology (phenotype C).
“A high AMH means excellent fertility.” Not necessarily. In PCOS high AMH reflects follicle number and may coincide with anovulation.
“I must lose weight before treatment.” Not required in every case; the guideline recommends lifestyle support alongside, not instead of, appropriate treatment.
“Metformin alone is the best fertility drug.” No. Letrozole is more effective for ovulation induction.
“If clomiphene failed, nothing will work.” Incorrect. Letrozole, gonadotrophins, drilling and IVF remain options.

Frequently Asked Questions

Can PCOS cause infertility even if my periods are regular?

Yes, though it is less likely. Regular cycles usually indicate ovulation, but PCOS with regular cycles can coexist with other fertility factors. If you have not conceived within the recommended time, assessment is still appropriate.

Can I get pregnant naturally with PCOS?

Yes. Many women do, particularly those who ovulate at least occasionally. Chances depend on how often you ovulate, your age, your tubes and uterus, and your partner’s sperm health.

Do I need IVF if I have PCOS?

No, not automatically. IVF is usually a later step after ovulation induction, or earlier if another factor requires it.

Is letrozole safe for getting pregnant?

It is recommended as first-line treatment by the 2023 international guideline when prescribed and monitored by a clinician. Large trials found no significant difference in overall congenital anomalies compared with clomiphene, and it carries a lower twin rate. Never take it without prescription and monitoring.

How long does it take to get pregnant with PCOS?

There is no single answer. Treatment is generally tried for a limited number of cycles, and the trial that established letrozole’s benefit used up to five cycles. Your doctor should reassess if pregnancy does not occur.

Does PCOS increase miscarriage risk?

The 2024 meta-analysis found higher odds of miscarriage in PCOS, but the individual risk depends on age, metabolic health and other factors. Recurrent loss deserves its own evaluation rather than being attributed to PCOS by default.

Can unmarried women have PCOS?

Yes. PCOS does not depend on marriage or sexual activity, and symptoms such as irregular periods, acne or excess hair growth deserve assessment at any age. In teenagers, diagnosis requires extra care.

Will PCOS go away?

No permanent cure exists, but symptoms can be managed, and some women find cycles regularise with lifestyle change, treatment or age. Read more about PCOS and fertility.

What to Do Next

If you have PCOS or suspect it and want to conceive, the most useful first steps are to:

Confirm the diagnosis and rule out look-alike conditions
Check whether you are ovulating
Have a glucose tolerance test and basic metabolic check
Arrange semen analysis for your partner
Ask whether tubal assessment is needed in your situation

From there, treatment can be tailored: lifestyle support, letrozole as first-line ovulation induction, and escalation only if needed.

Plan Your Assessment at Kamran Fertility Clinic

Dr. Kamran Saleem offers unhurried, doctor-led consultations in Lahore, including second opinions on earlier treatment. A good starting point is the fertility assessment and diagnosis service, which covers hormonal analysis and ovulation testing for women and semen analysis for male partners.

Clinic locations:

Rasheed Hospital: Main Boulevard, DHA Defence, Lahore
TAMC: M.M. Alam Road, Lahore
Shahnaz Hospital: Shalamar Link Road, Lahore

Book a consultation on WhatsApp: +92 314 8432789.

If you already have fertility reports, hormone results or previous treatment records, bring them to your consultation. They can help avoid repeating unnecessary tests.

Key takeaway: PCOS makes ovulation less predictable, not impossible. Modern evidence points to a clear pathway, with letrozole as first-line treatment, individualised metabolic care, and attentive pregnancy monitoring, that gives most women a realistic route to a healthy pregnancy.

References

Teede HJ, et al. Recommendations from the 2023 international evidence-based guideline for the assessment and management of polycystic ovary syndrome. Fertility and Sterility / Human Reproduction / Journal of Clinical Endocrinology and Metabolism, 2023.
Legro RS, et al. Letrozole versus clomiphene for infertility in the polycystic ovary syndrome. N Engl J Med. 2014;371:119-129. DOI: 10.1056/NEJMoa1313517.
Bahri Khomami M, et al. Systematic review and meta-analysis of pregnancy outcomes in women with polycystic ovary syndrome. Nat Commun. 2024;15. DOI: 10.1038/s41467-024-49749-1.
Boomsma CM, et al. A meta-analysis of pregnancy outcomes in women with polycystic ovary syndrome. Hum Reprod Update. 2006;12(6):673-683.
Comparative outcomes of letrozole versus clomiphene citrate for ovulation induction in patients with PCOS: systematic review and meta-analysis. JBRA Assist Reprod. 2026;30(1):146-159.
Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process. The Lancet, 2026. DOI: 10.1016/S0140-6736(26)00717-8.
Mutsaerts MAQ, et al. Randomized trial of a lifestyle program in obese infertile women (LIFEstyle). N Engl J Med. 2016;374:1942-1953.
World Health Organization. Guideline for the prevention, diagnosis and treatment of infertility. 2025.

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