Egg: The female reproductive cell produced in and released from the ovaries; also called the ovum.
Emergency Contraception (EC): Methods that are used to prevent pregnancy after a woman has had sex without birth control, after the method she used has failed, or if a woman is raped. Emergency contraception methods include progestin-only pills, ulipristal, birth control pills taken in specific amounts, or a copper intrauterine device. The pills must be taken within 5 days of unprotected sex to reduce the risk of pregnancy.
Estrogen: A female hormone produced in the ovaries.
Hormone: A substance made in the body by cells or organs that controls the function of cells or organs. An example is estrogen, which controls the function of female reproductive organs.
Intrauterine Device (IUD): A small device that is inserted and left inside the uterus to prevent pregnancy.
Menstrual Cycle: The monthly process of changes that occur to prepare a woman’s body for possible pregnancy. A menstrual cycle is defined from the first day of menstrual bleeding of one cycle to the first day of menstrual bleeding of the next cycle.
Ovulation: The release of an egg from one of the ovaries.
Progesterone: A female hormone that is produced in the ovaries and that prepares the lining of the uterus for pregnancy.
Progestin: A synthetic form of progesterone that is similar to the hormone produced naturally by the body.
Sexual Intercourse: The act of the penis of the male entering the vagina of the female (also called “having sex” or “making love”).
Sexually Transmitted Infections: Infections that are spread by sexual contact, including chlamydia, gonorrhea, human papillomavirus infection, herpes, syphilis, and infection with human immunodeficiency virus (HIV, the cause of acquired immunodeficiency syndrome [AIDS]).
Sperm: A cell produced in the male testes that can fertilize a female egg.