Hormonal Contraception Information

Estrogen and progesterone (progestin) are hormones used in many forms of birth control (contraception). These two hormones make up most hormonal contraceptives. Hormonal contraceptives use either:

  • A combination of estrogen hormone and progesterone hormone in one of these forms: 

  • Pill—Pills come in various combinations of active hormone pills and nonhormonal pills. Different combinations of pills may give you a period once a month, once every 3 months, or no period at all. It is important to take the pills the same time each day.

  • Patch—The patch is placed on the lower abdomen every week for 3 weeks. On the fourth week, the patch is not placed.

  • Vaginal ring—The ring is placed in the vagina and left there for 3 weeks. It is then removed for 1 week.

  • Progesterone alone in one of these forms:

  • Pill—Hormone pills are taken every day of the cycle.

  • Intrauterine device (IUD)—The IUD is inserted during a menstrual period and removed or replaced every 5 years or sooner.

  • Implant—Plastic rods are placed under the skin of the upper arm. They are removed or replaced every 3 years or sooner.

  • Injection—The injection is given once every 90 days.

Pregnancy can still occur with any of these hormonal contraceptive methods. If you have any suspicion that you might be pregnant, take a pregnancy test and talk to your health care provider.

ESTROGEN AND PROGESTERONE CONTRACEPTIVES

Estrogen and progesterone contraceptives can prevent pregnancy by:

  • Stopping the release of an egg (ovulation).

  • Thickening the mucus of the cervix, making it difficult for sperm to enter the uterus.

  • Changing the lining of the uterus. This change makes it more difficult for an egg to implant.

Side effects from estrogen occur more often in the first 2–3 months. Talk to your health care provider about what side effects may affect you. If you develop persistent side effects or they are severe, talk to your health care provider.

PROGESTERONE CONTRACEPTIVES

Progesterone-only contraceptives can prevent pregnancy by:

  • Blocking ovulation. This occurs in many women, but some women will continue to ovulate.  

  • Preventing the entry of sperm into the uterus by keeping the cervical mucus thick and sticky.  

  • Changing the lining of the uterus. This change makes it more difficult for an egg to implant.  

Side effects of progesterone can vary. Talk to your health care provider about what side effects may affect you. If you develop persistent side effects or they are severe, talk to your health care provider.