Infertility is the situation where couples of reproductive age cannot achieve pregnancy despite regular sexual intercourse for one year or cannot sustain an existing pregnancy. Primary infertility is the absence of pregnancy, while secondary infertility is the absence of pregnancy despite a previous pregnancy. Infertility is a global health problem affecting 9% to 30% of couples.Reproduction depends on factors such as the couple's age, frequency and time of sexual intercourse. The reproductive capacity of women begins to decline after the age of 30, and of men after the age of 40. Various physiological elements are necessary for pregnancy in both sexes; appropriate cervical mucus, open fallopian tubes and normal ovulation in women, and healthy sperm production and no obstruction of the genital system in men are important.Factors that cause infertility include age, sexually transmitted diseases, alcohol and smoking, environmental factors and psychological conditions. Various tests are performed for the diagnosis of infertility, including semen analysis, hormonal tests and imaging methods. Treatment can be done surgically or medically, depending on the underlying cause, and most couples can have children with treatment.