Prolactin is a hormone synthesized by the pituitary gland and plays a key role in the reproductive system. During pregnancy, it prepares the mammary glands for lactation, and after childbirth, it aids in milk synthesis. Prolactin inhibits ovulation, as breastfeeding can delay the return of the menstrual cycle. Although primarily associated with women, men and non-pregnant women also produce prolactin with various functions. Elevated levels may result from various issues such as tumors or medications, while low levels are associated with pituitary dysfunction.