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Risks and side effects associated with estrogen-progestin contraceptives

Kathryn A Martin, MD
Pamela S Douglas, MD
Section Editors
Robert L Barbieri, MD
William F Crowley, Jr, MD
Deputy Editor
Kathryn A Martin, MD


Oral contraceptives (OCs) are a reliable form of contraception with a theoretical failure rate of 0.1 percent and, due to problems with compliance, an actual failure rate of 2 to 3 percent. They also have noncontraceptive benefits, being useful in the treatment of a variety of disorders including hyperandrogenism, dysmenorrhea, and menorrhagia. Currently available preparations are shown in the table (table 1). There are, however, several contraindications to their use. (See "Overview of the use of estrogen-progestin contraceptives".)

Concern about toxicity (such as thromboembolic events and cardiovascular disease) initially limited the long-term use of these drugs. However, the decrease in both estrogen and progestin content since the introduction of the pill in 1960 has led to a reduction in both side effects and cardiovascular complications [1]. As a result, these preparations are a reasonable contraceptive option for most women.

While the US Food and Drug Administration (FDA) had previously set upper age limits for OC use as 35 years for smokers and 40 years for nonsmokers, the age limit was removed in 1989 for healthy, nonsmoking women. Thus, OCs can be given until menopause in such women. Caution is still needed in prescribing OCs for women who smoke and an effort to induce smoking cessation should be made first.

Certain forms of toxicity remain a concern. This topic will review the side effects and major potential risks associated with OC administration. The noncontraceptive benefits of estrogen-progestin contraceptives and other types of contraception are reviewed separately. (See "Overview of the use of estrogen-progestin contraceptives", section on 'Noncontraceptive benefits' and "Contraceptive counseling and selection".)


Early side effects of oral contraceptives (OCs) include bloating, nausea, and breast tenderness [2]. Although they may be bothersome enough to lead to discontinuation of the OC, these side effects usually subside in several months. Abnormal bleeding is a common problem that often resolves. Weight gain is not a consistent finding with low-dose pills. (See 'Weight' below.)

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Literature review current through: Nov 2017. | This topic last updated: Aug 22, 2016.
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