How Birth Control Methods Prevent Pregnancy

Topic Overview

Birth control methods

Method

How it prevents pregnancy


Hormonal


  • Prevents ovulation
  • Thickens mucus at the cervix so sperm cannot pass through
  • Changes the environment of the uterus and fallopian tubes to prevent fertilization and to prevent implantation if fertilization occurs

Intrauterine device (IUD)


  • There are two types of IUDs (hormonal and copper). Both types may work by preventing:
    • Fertilization of the egg.
    • Implantation in the uterus.

Barrier methods


  • Block sperm from reaching the egg
  • Some are used with spermicides, which kill sperm.

Fertility awareness (natural family planning)


  • Identifies the time during a woman's cycle when she is most likely to become pregnant (fertile). An extra method or abstinence should be used during this time of fertility.

Permanent birth control (sterilization)


Related Information

Credits

ByHealthwise Staff
Primary Medical Reviewer Sarah A. Marshall, MD - Family Medicine
Anne C. Poinier, MD - Internal Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
Elizabeth T. Russo, MD - Internal Medicine
Specialist Medical Reviewer Femi Olatunbosun, MB, FRCSC, FACOG - Obstetrics and Gynecology, Reproductive Endocrinology

Current as ofNovember 21, 2017

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