morning-after pill

drug

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Last updated

June 17, 2026

Quick Summary

The morning-after pill is an oral drug, typically containing high doses of estrogen, used to prevent pregnancy after unprotected sexual intercourse or contraceptive failure. It is ideally taken within 72 hours and works by delaying ovulation or preventing implantation. It cannot terminate an existing pregnancy.1

Levonorgestrel, a synthetic progestogen, is a key component in some morning-after pills. It functions by inhibiting ovulation, thickening cervical mucus to block sperm, and potentially preventing implantation.2

The morning-after pill is a form of emergency contraception. It is important to note that while effective in preventing pregnancy, it does not protect against sexually transmitted diseases.23

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contraception
Hormonal contraceptives
The “morning-after pill”—a series of pills containing either high dosages of both estrogen and progestogen (any progestational steroid, such as progesterone) or only progestogen—is one of the few methods for preventing pregnancy after intercourse.
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The “morning-after pill”—a series of pills containing either high dosages of both estrogen and progestogen (any progestational steroid, such as progesterone) or only progestogen—is one of the few methods for preventing pregnancy after intercourse.
Read More

levonorgestrel
…span between menstruations—and in a morning-after pill called Plan B. In 1999 Plan B became available by prescription in the United States. In 2006, after a long politically charged debate, the U.S. Food and Drug Administration approved the sale of Plan B to women (and men) aged 18 and older…
Read More
…span between menstruations—and in a morning-after pill called Plan B. In 1999 Plan B became available by prescription in the United States. In 2006, after a long politically charged debate, the U.S. Food and Drug Administration approved the sale of Plan B to women (and men) aged 18 and older…
Read More

Roman Catholicism
The family
…proscribed Catholics from taking the “morning-after” pill, because its use manifests the intention to commit abortion; denounced in vitro fertilization, because it disrupts the natural process of conception; and condemned medical research using embryonic stem cells, though it endorsed research with adult stem cells. While many theologians, clergy, and
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…proscribed Catholics from taking the “morning-after” pill, because its use manifests the intention to commit abortion; denounced in vitro fertilization, because it disrupts the natural process of conception; and condemned medical research using embryonic stem cells, though it endorsed research with adult stem cells. While many theologians, clergy, and
Read More