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First-trimester medication abortion (termination of pregnancy)

Author
Bryna Harwood, MD, MS
Section Editor
Jody Steinauer, MD, MAS
Deputy Editor
Sandy J Falk, MD, FACOG

INTRODUCTION

Medication abortion (also referred to as medical abortion) is the termination of pregnancy with use of medications alone rather than surgery. Mifepristone, an antiprogestin, is approved for use in the United States, in combination with misoprostol, for the termination of pregnancies up to 70 days of gestation. First-trimester medication abortion beyond 70 days is associated with a lower efficacy and requires in-hospital supervision.

The use of mifepristone in combination with misoprostol for medication termination of pregnancy in the first trimester is reviewed here. Use of misoprostol alone for medication abortion and other methods of pregnancy termination are discussed separately. (See "Misoprostol as a single agent for medical termination of pregnancy" and "Overview of pregnancy termination".)

MEDICATION VERSUS SURGICAL TERMINATION

Medication and surgical (uterine dilation and suction aspiration) abortion are both safe and effective approaches for appropriately selected patients [1]. The choice is based upon availability, gestational age (medication abortion is less successful in the late first trimester), and patient preference. Women seeking abortion care should be counseled about the advantages and disadvantages of both options.

Prior to 2000, Medication abortion in the first trimester was available only using a prostaglandin with or without methotrexate. Since 2000, medication abortion with mifepristone and misoprostol was approved for use by the US Food and Drug Administration (FDA) in the United States. Surgical abortion is still performed in the majority of cases and also in cases in which medication abortion is incomplete. The United States Centers for Disease Control and Prevention (CDC) reported that, in 2009, 16.2 percent of abortions at ≤8 weeks of gestation and 0.9 percent at >8 weeks were performed with medication alone [2].

First-trimester surgical abortion is effective in terminating pregnancy in 98 to 99 percent of procedures and has a complication rate of 0 to 3 percent [3]. The major complications of surgical abortion are incomplete evacuation, uterine perforation, problems related to anesthesia, and endometritis. (See "Surgical termination of pregnancy: First trimester", section on 'Complications'.)

                                             

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