Does providing women with emergency oral contraception in advance for use as needed change pregnancy rates, frequency and timing of contraceptive use, risk of sexually transmitted infections, or sexual behavior?
Providing oral emergency contraceptives in advance to fertile women for use after unprotected sexual intercourse (i.e., advance provision) does not affect pregnancy rates, condom use, sexually transmitted infection rates, or type of contraception used. Advance provision more than doubles the odds that a woman will use emergency contraception once and more than quadruples the odds that she will use it two or more times. It also reduces the time from sexual intercourse to emergency contraceptive use by about 15 hours.
To increase the availability and use of emergency contraception, the American College of Obstetricians and Gynecologists recommends one 1.5-mg dose of levonorgestrel (Plan B) or two 0.75-mg doses taken 12 to 24 hours apart for women who have had unprotected or inadequately protected sexual intercourse.1 This practice guideline supports advance provision. The American Academy of Pediatrics has a similar policy.2 The American Academy of Family Physicians does not specifically address advance provision.3 Although combined contraceptive pills and mifepristone (Mifeprex) can be used for emergency contraception, levonorgestrel is better tolerated, is more effective, and is approved by the U.S. Food and Drug Administration for over-the-counter distribution.
This Cochrane review included randomized controlled trials comparing advance provision with standard access to emergency contraception. The review included eight trials (6,389 total participants); five of the trials were conducted in the United States. Two studies had the power to show a difference in pregnancy rates. Control groups received general contraceptive counseling, information about emergency contraceptives, and/or access to emergency contraception on request. Most of the trials provided one to three courses of levonorgestrel and followed patients for three to 12 months.
No study found a difference in pregnancy rates. Women who had advanced access to emergency contraception were about 2.5 times more likely to use it once and over four times more likely to use it two or more times. These women were also more likely to take the contraception an average of about 15 hours sooner after sexual intercourse than those in the control groups. The three studies that measured rates of sexually transmitted infections did not find a difference between groups. The five studies that reported on contraception use did not find differences between groups in the type or frequency of contraception use, including condom use. The six studies that compared frequency of unprotected sexual intercourse did not find a difference between groups. No adverse events were reported in any of the studies.
Although most women took the first contraceptive pill as directed, in one study, 17 percent of women who received advanced access took the second pill incorrectly. Therefore, single-dose regimens may be preferable. Providing women with advanced access to emergency contraception appears to be safe but does not reduce pregnancy rates on a population level. However, individual women might benefit because advance provision increases the speed and frequency of contraceptive use.