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What hormones are found in combination birth control pills?

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Blister pack of 28 oral contraceptive pills arranged in four rows, with 21 white active pills followed by 7 orange inactive pills. Arrows indicate the order for taking pills. — birth control A 28-day package of birth control pills.

Combination birth control pills contain two synthetic steroid hormones: estrogen and progestin (a synthetic form of progesterone).123

By maintaining high levels of these hormones, the combination pill suppresses the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. This process prevents ovulation, thereby preventing the release of an egg for fertilization.12