Infertility affects over 7 million American women of childbearing age, according to the Centers for Disease Control and Prevention. Infertility is a broad term used to describe the impaired ability to conceive children. According to the National Library of Medicine (NLM), healthy couples under age 30 have a 25 to 30 percent chance of becoming pregnant every month, as long as they are having regular sex. Primary infertility describes couples who have unsuccessfully conceived after at least one year of unprotected sex. Some couples may have achieved pregnancy at least once but could not thereafter — a condition known as secondary infertility. Women who can become pregnant but are unable to carry the child until birth may also be infertile. A number of factors can contribute to infertility, and the causes may vary between men and women. While infertility happens for a great number of reasons, a combination of medical intervention and lifestyle changes may lead to a successful pregnancy.

Female infertility
Women reach their peak fertility age around their early 20s, but beginning around ages 35 to 40, a woman is significantly less likely to get pregnant. There are many factors that can lead to infertility. In order for a fertilized egg to grow successfully in the womb, it must be released by a woman’s ovaries, stick to the lining of the uterus and survive. Infertility may occur if the ovaries have difficulty producing eggs in the first place.

These challenges to fertility can be caused by lifestyle habits or underlying health problems. Hormonal disorders such as thyroid disease or abnormal hormone levels may lead to infertility. Chronic diseases including autoimmune disorders, diabetes, cancer and endometriosis also make it harder to conceive, as can problems within or around the genital area, such as ovarian cysts or pelvic inflammatory disease. Eating disorders, poor nutrition, obesity and substance abuse may all contribute to infertility in both men and women.

Male infertility
Male infertility can result from a low sperm count, which means the testes have produced less sperm than normal. The sperm may also have been unable to exit the testes, or they might not function quite right. Male infertility may result from a number of factors including: underlying health conditions, environmental pollutants and retrograde ejaculation. Extreme weather conditions can also damage sperm in the testes.

Testing for infertility
Women and men undergo drastically different tests to diagnose infertility. Tests for men are generally less invasive, and they include sperm testing or a rarely performed testicular biopsy. Infertility testing for women may entail blood tests, a pelvic ultrasound or an X-ray of the uterus and fallopian tubes that involves the injection of dye through the cervix.

The course of treatment will vary depending on the underlying cause. According to the NLM, as many as one in five couples diagnosed with infertility can conceive a baby without treatment. Having sex at least every three days before and during ovulation can increase the chances of pregnancy. For some people, long-term lifestyle changes including a healthy diet and exercise may restore fertility. Procedures such as intrauterine insemination and in-vitro fertilization can help a couple conceive a baby without sex. With treatment, over half of couples diagnosed with infertility can become pregnant.