The human reproductive system is a complex one. The intricate and detailed processes involving ovulation and fertilization have to coordinate just right in order for pregnancy to occur.
Within every 28-day menstrual cycle, the ovaries in a woman’s body prepare eggs for release, a process called ovulation. For a pregnancy to occur, a sperm must unite with an egg in the fallopian tube within about 24 hours after the egg’s release. If fertilized, the egg must move into the uterus where it attaches to the uterine lining and begins a nine-month growing process.
Many factors can affect the process and prevent pregnancy.
On the male side, infertility can be due to impaired production or function of the sperm, impaired movement of sperm, low sperm concentration, genetic defects and infections, or impaired delivery of the sperm due to abnormal ejaculation, the absence of semen or blockage of ejaculatory ducts. A man’s general health and lifestyle may also affect his fertility.
As for women, their fertility can be affected by fallopian tube damage or blockage, ovulation disorders, early menopause, abnormal hormone production or health and lifestyle issues. Some women may contract endometriosis, a condition in which uterine tissue grows outside of the uterus, affecting the function of the ovaries, uterus and fallopian tubes.
The main sign of infertility is the inability of a couple to get pregnant. In some cases, an infertile woman may have abnormal menstrual periods. An infertile man may exhibit signs of hormonal problems such as changes in hair growth or sexual function.
Many of the risk factors for women and men are similar. These include:
- Age. For women, their fertility begins to gradually decline after about age 32 with older women more likely to experience health issues involving fertility. Men over age 40 tend to be less fertile than younger men.
- Tobacco smoking, caffeine consumption and alcohol use.
- Being overweight or underweight.
- Too much exercise. Some studies show that women who exercise more than seven hours a week may experience ovulation issues.