Citation: Mechanism of Action of Hormonal Contraceptives -Basic and Clinical Pharmacology 11th ed (Katzung)

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Mechanism of Action of Hormonal Contraceptives

“The combinations of estrogens and progestins exert their contraceptive effect largely through selective inhibition of pituitary function that results in inhibition of ovulation. The combination agents also produce a change in the cervical mucus, in the uterine endometrium, and in motility and secretion in the uterine tubes, all of which decrease the likelihood of conception and implantation. The continuous use of progestins alone does not always inhibit ovulation. The other factors mentioned, therefore, play a major role in the prevention of pregnancy when these agents are used.”

Basic and Clinical Pharmacology 11th edition (Bertram G. Katzung, Susan B. Masters, Anthony J. Trevor (c) 2009, McGraw Hill Companies Inc)