Causes of Infertility in Women: 9 Common Reasons and What You Can Do

Trying to conceive without success can leave you with many questions. You might have regular periods, feel healthy, and still wonder why pregnancy hasn’t happened. Or perhaps you’ve noticed irregular menstrual cycles, painful periods, or other changes that concern you.

The causes of infertility in women vary, and understanding them is the first step towards getting the right support.

Female infertility can result from problems with ovulation, hormonal imbalances, blocked or damaged fallopian tubes, endometriosis, uterine conditions such as fibroids, or age-related changes in egg quantity and quality. Sometimes, no clear cause is identified, even after medical investigations. Fertility problems can also involve the male partner, which is why both partners should be assessed where applicable.

If you’re struggling to conceive, you don’t have to rely on guesswork. A fertility evaluation can help identify possible problems and guide your next steps.

What Is Female Infertility?

Female infertility refers to difficulty achieving pregnancy because of factors affecting the female reproductive system. These may involve the ovaries, fallopian tubes, uterus, or the hormones that regulate reproduction.

The World Health Organization defines infertility as the failure to achieve pregnancy after 12 months or more of regular, unprotected sexual intercourse. However, you may need an evaluation sooner depending on your age, medical history, or symptoms.

Infertility can be:

• Primary infertility: When a person has never achieved a pregnancy.
• Secondary infertility: When a person has previously achieved a pregnancy but is now experiencing difficulty conceiving again.

Having conceived before doesn’t mean you cannot experience fertility difficulties later. Equally, a diagnosis of infertility doesn’t automatically mean pregnancy is impossible. The outlook depends on the underlying cause and other individual factors.

9 Common Causes of Infertility in Women

Several conditions can interfere with the processes required for pregnancy, from releasing an egg to allowing a fertilised egg to implant in the uterus.

1. Ovulation Problems

Ovulation is the process in which an ovary releases an egg during the menstrual cycle. For pregnancy to occur naturally, an egg must be released, fertilised by sperm, and successfully implant in the uterus.

When ovulation doesn’t happen regularly, or doesn’t happen at all, conception can become difficult.

Possible signs of ovulation problems include:

• Irregular menstrual periods.
• Periods that stop for several months.
• Unusually long or unpredictable menstrual cycles.
• Difficulty identifying fertile days.

Some women experience few noticeable symptoms, so the absence of obvious signs doesn’t necessarily mean ovulation is occurring normally.

Ovulation problems can have several causes, including polycystic ovary syndrome, thyroid disorders, and conditions affecting the hormones that control the ovaries.

2. Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a hormonal condition that can interfere with normal ovulation. It is a common cause of fertility difficulties in women.

PCOS may affect how the ovaries develop and release eggs. Some women with the condition ovulate irregularly, while others may not ovulate consistently enough to conceive easily.

Possible symptoms include:

• Irregular or absent periods.
• Excess facial or body hair.
• Acne.
• Thinning hair on the scalp.
• Difficulty managing weight in some cases.

Not every woman with PCOS experiences all these symptoms. A diagnosis usually involves assessing symptoms, medical history, and appropriate clinical investigations.

Can you get pregnant with PCOS?

Yes. Many women with PCOS conceive, either naturally or with medical assistance. Treatment depends on individual circumstances and may include managing associated health conditions or medication to support ovulation.

Having PCOS doesn’t automatically mean you are infertile.

3. Blocked or Damaged Fallopian Tubes

The fallopian tubes connect the ovaries to the uterus. They provide the pathway through which sperm and an egg can meet and through which an early embryo travels towards the uterus.

If one or both tubes are blocked or damaged, fertilisation or the movement of the embryo may be affected.

Common causes of tubal damage include:

• Pelvic inflammatory disease (PID).
• Certain sexually transmitted infections, including chlamydia.
• Previous pelvic or abdominal surgery.
• Scar tissue from previous infections or inflammation.
• Complications associated with some pelvic conditions.

One challenge is that blocked fallopian tubes may not cause noticeable symptoms. A woman may only discover the problem during a fertility evaluation.

Doctors may recommend a hysterosalpingogram (HSG), an imaging test that uses contrast dye and X-rays to assess the uterus and whether the fallopian tubes are open.

When tubal damage is identified, the appropriate treatment depends on its location and severity. In some circumstances, in vitro fertilisation (IVF) may be considered because it allows fertilisation to take place outside the body.

4. Endometriosis

Endometriosis occurs when tissue similar to the lining of the uterus grows outside the uterus. It can cause inflammation, pain, and scar tissue in the pelvic area.

Depending on its location and severity, endometriosis may affect the ovaries, fallopian tubes, and other structures involved in reproduction.

Symptoms can include:

• Painful menstrual periods.
• Persistent pelvic pain.
• Pain during or after sexual intercourse.
• Pain when passing stool or urine during menstruation.
• Difficulty conceiving.

Some women with endometriosis experience few symptoms, while others have significant pain.

Endometriosis can affect fertility in different ways, and its presence doesn’t automatically mean pregnancy is impossible. A specialist can assess the condition and discuss appropriate treatment options based on symptoms, age, reproductive goals, and other findings.

5. Uterine Fibroids and Other Uterine Conditions

The uterus plays an essential role in pregnancy because a fertilised egg needs to implant in its lining and develop there.

Conditions affecting the shape or internal environment of the uterus may sometimes interfere with conception or pregnancy.

Uterine fibroids are non-cancerous growths that develop in or around the uterus. Their effect on fertility depends on factors such as their size, number, and location.

Fibroids that distort the uterine cavity may interfere with implantation or increase certain pregnancy risks. Other fibroids may have little or no effect on fertility.

Additional uterine conditions that may require investigation include:

• Endometrial polyps, which are growths in the uterine lining.
• Intrauterine adhesions, which are bands of scar tissue inside the uterus.
• Certain congenital differences in uterine shape.

Possible symptoms of uterine conditions include heavy menstrual bleeding, prolonged periods, pelvic pressure, or difficulty conceiving. However, symptoms alone cannot establish the cause.

Depending on the findings, a doctor may recommend an ultrasound scan or hysteroscopy to examine the uterine cavity. Treatment is individualised; not every fibroid or polyp needs to be removed.

6. Hormonal Imbalances and Thyroid Disorders

Hormones regulate several reproductive processes, including the development of eggs, ovulation, and the menstrual cycle.

When hormone levels are outside their normal range, these processes may be disrupted.

Conditions that can affect female fertility include:

• Thyroid disorders: Both an underactive and an overactive thyroid can interfere with menstrual function and fertility.
• Elevated prolactin: High levels of this hormone can disrupt ovulation.
• Hypothalamic or pituitary disorders: Problems involving these parts of the brain may affect the hormonal signals that regulate the ovaries.
• Primary ovarian insufficiency: A condition in which the ovaries lose normal function before age 40.

Hormonal problems may cause irregular periods, absent periods, or other symptoms, although some women have few obvious signs.

A fertility specialist may recommend targeted blood tests based on your menstrual history, symptoms, and examination. The aim is to identify relevant abnormalities rather than order every possible hormone test indiscriminately.

7. Age-Related Decline in Fertility

Age is an important factor affecting female fertility.

Women are born with a finite supply of eggs. As they get older, the number of remaining eggs declines, and the proportion of eggs with chromosomal abnormalities increases.

Fertility generally begins to decline more noticeably during the mid-30s, with a more pronounced decline as women approach their 40s.

Age can affect:

• The likelihood of conceiving naturally.
• Egg quantity and quality.
• The risk of miscarriage.
• The likelihood of success with some fertility treatments.

This doesn’t mean every woman in her late 30s or 40s will experience infertility. Individual circumstances differ, but age is an important consideration when deciding whether to seek an assessment.

If you’re over 35 and have been trying to conceive for six months without success, consider a fertility evaluation. If you’re over 40, seeking advice promptly is generally appropriate.

8. Premature Ovarian Insufficiency and Reduced Ovarian Reserve

The ovaries contain the eggs available for potential future pregnancies. Two related but distinct concepts can help explain changes in ovarian function.

Reduced ovarian reserve means the remaining supply of eggs is lower than expected or has declined. It doesn’t necessarily mean that a woman cannot conceive naturally.

Primary ovarian insufficiency (POI) occurs when the ovaries stop functioning normally before age 40. It may lead to irregular or absent periods and reduced fertility.

Possible contributors to impaired ovarian function include genetic conditions, autoimmune conditions, previous chemotherapy or radiation, and some surgical procedures. In many cases, the cause is not identified.

Tests such as anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), and an ultrasound assessment of antral follicle count may help a specialist evaluate ovarian reserve.

However, these tests have limitations. Ovarian reserve results do not independently determine whether a woman can conceive naturally, and they cannot guarantee how successful fertility treatment will be.

9. Lifestyle, Medical History, and Unexplained Infertility

Some lifestyle factors and medical treatments can influence reproductive health, while other fertility difficulties remain unexplained.

Factors worth discussing with a clinician include:

• Very low or high body weight: Either can affect hormonal regulation and ovulation in some women.
• Smoking: Smoking is associated with poorer reproductive outcomes.
• Excessive exercise or inadequate nutrition: These may disrupt the hormones responsible for ovulation.
• Certain medical treatments: Chemotherapy and radiation can damage eggs or affect ovarian function.
• Chronic medical conditions: Some conditions and their treatments may influence fertility.

Stress can make the experience of trying to conceive more difficult, but infertility should not simply be blamed on stress. Relaxation alone cannot correct a blocked fallopian tube, remove a uterine polyp, or resolve every ovulation disorder.

Sometimes, testing doesn’t reveal a clear reason for difficulty conceiving. This is known as unexplained infertility. It doesn’t mean the problem is imaginary or that nothing can be done. It means that standard investigations have not identified a specific cause.

A fertility specialist can explain which options may be reasonable based on your age, reproductive history, how long you’ve been trying, and the results of your investigations.

What Are the Signs of Infertility in Women?

There isn’t one symptom that confirms infertility. Some women have an underlying condition with obvious symptoms, while others have regular periods and no noticeable warning signs.

Possible reasons to seek a fertility assessment include:

• Difficulty conceiving after regular, unprotected sex.
• Irregular or absent menstrual periods.
• Severe menstrual cramps or persistent pelvic pain.
• Very heavy or prolonged menstrual bleeding.
• A history of pelvic inflammatory disease or a sexually transmitted infection.
• Known endometriosis, PCOS, or another condition that may affect fertility.
• Previous chemotherapy, radiation, or pelvic surgery that could affect reproductive function.

These symptoms don’t necessarily mean you are infertile. They indicate that a medical assessment may be useful.

How Are the Causes of Infertility in Women Diagnosed?

A fertility evaluation aims to identify problems that may be preventing conception. The investigations recommended will depend on your age, symptoms, medical history, and how long you’ve been trying to conceive.

Step 1: Review Your Medical and Menstrual History

Your clinician may ask about your menstrual cycle, previous pregnancies, miscarriages, pelvic infections, surgeries, medications, and family history.

Keeping a record of your periods and symptoms can help make this discussion more useful.

Step 2: Assess Ovulation and Hormonal Function

Depending on your circumstances, blood tests may be used to assess ovulation or investigate hormonal conditions. The timing of certain tests matters, so follow your clinician’s instructions.

Step 3: Examine the Uterus and Ovaries

A pelvic or transvaginal ultrasound may help identify fibroids, ovarian cysts, some features associated with PCOS, and other structural concerns.

Further tests may be recommended if the initial findings suggest a problem.

Step 4: Check Whether the Fallopian Tubes Are Open

An HSG or another appropriate imaging test may be used to assess the fallopian tubes and uterine cavity.

Not every woman needs every test. The choice depends on the clinical question being investigated.

Step 5: Evaluate Both Partners

Infertility can involve the female partner, the male partner, both partners, or factors that remain unexplained. A semen analysis is an important part of an appropriate fertility work-up when sperm are involved in conception.

Investigating both partners can prevent delays and help ensure that treatment addresses the relevant factors.

Find Out What May Be Affecting Your Fertility

Female infertility can have several causes, from ovulation disorders to blocked fallopian tubes. A fertility evaluation can help identify possible factors and guide the next steps. Speak with our fertility specialist at Doren Fertility Centre to discuss your concerns and explore appropriate care.

Can Female Infertility Be Treated?

In many cases, treatment options are available, but the right approach depends on the underlying cause.

Possible treatments include:

• Ovulation-induction medication: May help selected women who do not ovulate regularly.
• Treatment for hormonal conditions: Managing a thyroid disorder or another relevant condition may improve reproductive function.
• Surgery: Selected fibroids, polyps, adhesions, or other structural problems may be treated surgically when appropriate.
• Intrauterine insemination (IUI): Prepared sperm are placed inside the uterus around ovulation in suitable cases.
• In vitro fertilisation (IVF): Eggs are collected and fertilised in a laboratory, and an embryo is transferred into the uterus.
• Intracytoplasmic sperm injection (ICSI): A single sperm is injected directly into an egg during an IVF cycle when indicated.

Not every woman needs IVF, and no fertility treatment guarantees pregnancy. A specialist can explain the potential benefits, limitations, costs, and risks of the options appropriate to your circumstances.

When Should You See a Fertility Specialist?

Consider arranging a fertility evaluation if:

• You’re under 35 and haven’t conceived after 12 months of regular, unprotected sex.
• You’re 35 or older and haven’t conceived after six months of trying.
• You’re over 40 and planning a pregnancy or experiencing difficulty conceiving.
• You have irregular or absent periods, known endometriosis, previous pelvic infections, or another condition that may affect fertility.

You don’t need to wait for the usual time period if you already have a medical condition or history that raises concerns about fertility.

Seeking an assessment doesn’t mean you must immediately begin treatment. It gives you the information needed to make informed decisions.

Common Myths About Female Infertility

Myth 1: Regular periods always mean you’re fertile

Regular periods can be a reassuring sign, but they don’t confirm that the fallopian tubes are open, that the uterine cavity is normal, or that every aspect of fertility is healthy.

Myth 2: Infertility is always the woman’s problem

False. Fertility difficulties may involve either partner, both partners, or unexplained factors. Both partners should be considered during the evaluation.

Myth 3: If you’ve had a baby before, you can’t experience infertility

False. Secondary infertility can occur after a previous pregnancy. Age, changes in reproductive health, and other factors may affect the ability to conceive again.

Myth 4: Every woman with fibroids needs surgery

False. The effect of fibroids depends on their size, number, and location. Treatment decisions should be based on clinical findings and reproductive goals.

Myth 5: IVF is the only treatment for infertility

False. Depending on the cause, treatment may involve medication, management of an underlying condition, surgery, IUI, IVF, or other approaches. Some people may not need assisted reproduction.

Frequently Asked Questions About the Causes of Infertility in Women

Conclusion: Understanding the Cause Is the First Step

The causes of infertility in women are varied. Ovulation problems, PCOS, blocked fallopian tubes, endometriosis, fibroids, hormonal disorders, and age-related changes can all affect the chances of pregnancy. In some cases, no specific cause is identified.

The most useful next step is to understand what may be happening in your own situation rather than assume the worst or rely on unverified remedies.

A fertility evaluation can help identify possible causes and guide an appropriate care plan. With the right information and professional support, you can make informed decisions about your reproductive health and the options available to you.

If you’re finding it difficult to conceive, consider speaking with a qualified fertility specialist about your medical history, concerns, and next steps.