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The lower levels of estrogen in birth control pills suppress FSH and LH, "fooling" the pituitary gland into thinking a woman is pregnant. Ovulation will then not occur, which prevents pregnancy.
Review Date 3/31/2024
Updated by: LaQuita Martinez, MD, Department of Obstetrics and Gynecology, Emory Johns Creek Hospital, Alpharetta, GA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
