Infertility is the decline or lack of ability to generate offspring. Infertility does not mean a definitive inability to have children. The sterility of a couple is defined as the absolute inability to conceive a child.
Fertility varies from one person to another and from one couple to another. The diagnosis of infertility is made after two years of sexual intercourse without the use of a contraceptive method and not resulting in pregnancy. About 40% of the causes of infertility are due to women, 30% of men and 15% to both partners.