Health Conditions Can Reduce the Likelihood of Pregnancy

Couples also can have fertility problems because of health conditions in either the woman or the man. Common problems with a woman's reproductive organs, like uterine fibroids, endometriosis and pelvic inflammatory disease, can worsen with age and can also affect fertility. These conditions might cause the fallopian tubes to become blocked so the egg cannot travel into the uterus.

Some people have diseases or conditions that affect their hormone levels, which can cause infertility in women and impotence and infertility in men. Polycystic ovarian syndrome (PCOS) is a hormonal condition that affects many women, and it is the most common cause of anovulation, when a woman rarely or never ovulates.

Another hormonal condition that is a common cause of infertility is when a woman has a luteal phase defect (LPD). The luteal phase is the time in the menstrual cycle between ovulation and the start of the next menstrual period. LPD is a failure of the uterine lining to be fully prepared for a fertilized egg to implant. This happens either because a woman's body is not producing enough progesterone or because the uterine lining isn't responding to progesterone levels at some point in the menstrual cycle. Since pregnancy depends on a fertilized egg implanting in the uterine lining, LPD can interfere with getting pregnant or carrying a pregnancy successfully.

Certain lifestyle choices such as smoking, alcohol use, weighing much more or much less than an ideal body weight, too much strenuous exercise and having an eating disorder can also have a negative effect on a woman's fertility.

While some men remain fertile into their 60s and 70s, they might begin to have problems with the shape and movement of their sperm and a slightly higher risk of sperm gene defects. They might produce no sperm or too few sperm. Lifestyle choices also can affect the number and quality of a man's sperm. Alcohol and drugs can temporarily reduce sperm quality. Researchers are also looking at whether environmental toxins might play a role.