The most common causes of female infertility include fallopian tube damage or blockage, endometriosis, ovulation disorders, elevated prolactin, polycystic ovary syndrome (PCOS), early menopause, benign uterine fibroids and polyps, and pelvic adhesions (scar tissue). A brief overview of each is provided below. You may find more detailed information about these causes throughout the section, Causes of Infertility.

Fallopian Tube Damage Or Blockage
Fallopian tube damage usually results from inflammation of the fallopian tube (salpingitis). Chlamydia, a sexually transmitted disease, is the most frequent cause. Tubal inflammation may go unnoticed or cause pain and fever. Tubal damage is the major risk factor of a pregnancy in which the fertilized egg is unable to make its way through the fallopian tube to implant in the uterus, resulting in an ectopic pregnancy (pregnancy in the tube). One episode of tubal infection may cause fertility difficulties. The risk of ectopic pregnancy increases with each occurrence of tubal infection. Previous episodes of appendicitis and occasionally gall bladder infections can also cause infection to run down into the pelvis where the inflammation can damage the fallopian tubes.

Endometriosis
Endometriosis occurs when the uterine tissue implants and grows outside of the uterus; often affecting the function of the ovaries, uterus and fallopian tubes. These implants respond to the hormonal cycle and grow, shed and bleed in sync with the lining of the uterus each month. This can lead to pain, scarring and inflammation. Pelvic pain, painful menses, painful intercourse, and infertility are common in women with endometriosis.

Ovulation Disorders
Some cases of female infertility are caused by ovulation disorders. Disruption in the part of the brain that regulates ovulation can cause low levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) to reach the ovaries. Even slight irregularities in the hormone system can affect ovulation. Specific causes of hypothalamic-pituitary disorders include injury, tumors, excessive exercise and starvation or malnutrition.

Elevated Prolactin (Hyperprolactinemia)
The hormone prolactin stimulates breast milk production. High levels in women who aren't pregnant or nursing may affect ovulation. An elevation in prolactin levels may also indicate the presence of a pituitary tumor. In addition, some drugs can elevate levels of prolactin. Milk flow not related to pregnancy or nursing can be a sign of high prolactin. High prolactin is also sometimes completely silent, however, and only screening blood tests can determine if there is a problem.

Polycystic Ovary Syndrome (PCOS)
In PCOS, your body produces too much androgen hormone (testosterone) and insulin, which affects ovulation. PCOS is associated with insulin resistance (pre-diabetes) and obesity. Twenty percent of women with PCOS are actually slender and their diagnosis usually depends on menstrual patterns, blood tests, and ultrasound examinations of the ovaries.

Early Menopause (Premature Ovarian Failure)
Early menopause is the absence of menstruation and the early depletion of ovarian follicles before age 35. Although the cause is often unknown, certain conditions are associated with early menopause, including immune system diseases, radiation or chemotherapy treatment, and smoking.

Benign Uterine Fibroids And Endometrial Polyps
Fibroids are benign tumors in the wall of the uterus and are common in women in their 30s. Occasionally they may cause infertility by blocking the fallopian tubes. Fibroids are more common in women with African ancestry.

Polyps are generally benign (non-cancerous) growths of the lining of the uterus. Many polyps grow over the years as a result of chronic ovulation problems. Some form for no apparent reason.

Both fibroids and polyps can generally be treated surgically with excellent results.

Pelvic Adhesions
Pelvic adhesions are bands of scar tissue that bind organs after pelvic infection, appendicitis, or abdominal or pelvic surgery. The fallopian tubes work best when they can flow to and fro in the fluid currents within the pelvis. This scar tissue formation may impair fertility by pinning the tubes down and preventing their movements that are designed to find and catch drifting eggs.

Other Causes

A number of other causes can lead to infertility in women, including:

Medication
Temporary infertility may occur with the use of certain medications. In most cases, fertility is restored when the medication is stopped.

Thyroid Disorders And Thyroid Disease
Disorders and disease of the thyroid gland, either too much thyroid hormone (hyperthyroidism) or too little (hypothyroidism), can interrupt the menstrual cycle and cause infertility.

Infertility can also be seen when the body attacks its own thyroid gland: a condition called autoimmune thyroiditis or Hashimoto's Disease. This condition is frequently missed because its blood markers may come and go as the disease goes through cycles and flair ups.

Cancer And Its Treatment
Certain cancers, particularly female reproductive cancers, often severely impair female fertility. Both radiation and chemotherapy may affect a woman's ability to reproduce. Chemotherapy may impair reproductive function and fertility in women.

Medical Conditions
Medical conditions associated with delayed puberty or amenorrhea, such as Cushing's disease, sickle cell disease, HIV/AIDS, kidney disease and diabetes, can affect a woman's fertility.

Caffeine Intake
Excessive caffeine consumption may reduce fertility in the female, but the data are less clear. Moderate use of coffee or tea is probably not a big issue for most women.