Infertility is a condition or disease affecting the reproductive system that prevents successful pregnancy. It is typically diagnosed after a couple has had 12 months or regular (every 2-3 days) of unprotected, well-timed (around the time of ovulation) intercourse without a pregnancy occurring or when a woman has been unable to carry a pregnancy that results in a live birth.
Problems in fertility can occur at any point in the process of conception – in the development or release of the egg or sperm, in fertilisation or transport of the fertilised egg from the fallopian tube to the uterus, in implantation of the embryo in the uterine lining (the endometrium), even in the timing of intercourse or physical conditions after conception. In the female, the reproductive system consists of the vagina, cervix, uterus, fallopian tubes, ovaries, and vulva (the external structures). The male genital organs include the testicles, vas deferens, seminal vesicles, prostate gland, and penis. Hormones controlling reproduction and metabolism (produced by the hypothalamus, pituitary, and thyroid glands as well as the ovaries and testes) also play an important role.
In the UK approximately 1 in 7 couples have impaired fertility. The source of the infertility problem may be in either partner. Age can play an important role ― especially in women, but also in men. Endometriosis and the effects of sexually transmitted diseases may be factors in infertility. The presence of other diseases or infection in either partner can be a source of the problem. Nutritional, health, lifestyle choices, and environmental factors also have an effect. The most common defects reported are sperm disorders in men, and damaged or blocked tubes or ovulation problems in women. No cause is identified in up to one third of cases.
Risk factors for infertility include smoking, obesity, occupational risks, excessive alcohol and drug use. Psychological stress in either party may also contribute.
Infertility testing can be complex, expensive, and time-consuming. Often, both partners are required to undergo history taking, extensive physical examinations, blood tests, evaluation of lifestyles, and/or ultrasound testing to determine the source of the problem.