Conditions affecting the functioning of the female reproductive system including the ovaries, fallopian tubes, and uterus can lead to infertility. Female infertility can result from abnormalities of the female reproductive tract, implantation, and the ability to produce a fertilizable oocyte.

Primary infertility refers to females who have never been diagnosed with a clinical pregnancy and currently meet the criteria for infertility. Secondary infertility is the most common form of female infertility globally. It refers to a woman who has previously been diagnosed with a clinical pregnancy but presently cannot establish a clinical pregnancy—most of the time, secondary infertility results from reproductive tract infections.

Fecundity is a women’s biological ability to reproduce based on the monthly probability of conception. Impaired fecundity may affect twice as many couples as infertility. In the US, about 12% of women ages 15 to 44 have impaired fecundity or have difficulty getting pregnant or carrying a pregnancy to term.

The female reproductive tract abnormalities include tubal factors, peritoneal factors, uterine factors, cervical factors, and vaginal agenesis. Factors that cause abnormalities in implantation include luteal phase defect, hyperprolactinemia, insulin resistance, embryo-endometrial factors, and abnormalities of early embryogenesis. Factors affecting a female’s ability to produce a fertilizable oocyte include Ovulatory factors, gonadal dysgenesis, Turner’s syndrome, luteinized unruptured follicle syndrome, depletion of the oocyte pool from pelvic surgery, inflammatory losses, chemotherapy, and diseases such as endometriosis.

The major disease-related causes of female infertility include premature ovarian insufficiency, PCOS, endometriosis, uterine fibroids, and endometrial polyps. The most common cause of female infertility is PCOS which is a condition that impacts regular ovulation and causes anovulation or irregular ovulation. See PCOS and endometriosis for more information. Additionally, functional hypothalamic amenorrhea (FHA) is a condition that can cause anovulation and occurs from excessive exercise, weight loss, stress, or often a combination of these factors. Additionally, immunologic factors including autoimmune disease, antiphospholipid syndromes, thrombophilia, and recurrent pregnancy loss can cause infertility.

A woman’s risk of infertility increases with age, extreme weight gain, and loss, excessive physical or emotional stress that causes amenorrhea, and smoking and excessive alcohol use. The risk of female infertility increases with a BMI below 18.5 and a BMI equal to or greater than 25. Alcohol consumption during pregnancy is known to have adverse effects and cause fetal alcohol spectrum disorders, while the impact on fecundability is less understood. Chronic alcohol consumption may be associated with reduced fertility and an increased risk of developing menstrual disorders, although the exact mechanism for how alcohol affects fertility has yet to be determined. The World Health Organization (WHO) recommends women planning to conceive, and pregnant women should limit caffeine consumption to 200 to 300 mg per day or a maximum of two to three cups of coffee per day. It is unclear if there is an association between caffeine consumption and reduced fecundability or poor fertility treatment outcomes, however, 300 mg of caffeine per day does put one at a greater risk of spontaneous abortion.

Age is an essential factor for female fertility. Female fertility begins to decline around 25-30 years old. There is a direct correlation between age and the deterioration of the ovarian reserve and oocyte quality in females. A female is born with all of the oocytes she will have. As females age, the quantity and quality of oocytes begin to decline, and the continuous depletion of oocytes eventually leads to the onset of menopause.

Female infertility can be evaluated by a physician or other qualified health professional through proper history and physical examination. Additionally, ovulation can be tracked using basal body temperature (BBT) charting, which involves taking temperature first thing when waking before getting out of bed and plotting the temperatures to look for a sustained temperature rise that indicates ovulation has likely occurred. Basal body temperature charting is inexpensive and allows couples to understand the reproductive cycle and examine their fertility directly. Additionally, serum progesterone can be used to determine if ovulation has occurred.