April 2007

Advance provision of emergency contraception for pregnancy prevention (full review)

Polis CB, Schaffer K, Blanchard K, Glasier A, Harper CC, Grimes DA. Advance provision of emergency contraception for pregnancy prevention (full review). The Cochrane Library. April 2007; 2:1-25.

BACKGROUND: Emergency contraception can prevent pregnancy when taken after unprotected intercourse. Obtaining emergency contraception within the recommended time frame is difficult for many women. Advance provision, in which women receive a supply of emergency contraception before unprotected sex, could circumvent some obstacles to timely use.

OBJECTIVES: To summarize randomized controlled trials evaluating advance provision of emergency contraception to explore effects on pregnancy rates, sexually transmitted infections, and sexual and contraceptive behaviors.

SEARCH STRATEGY: In August 2006, we searched CENTRAL, EMBASE, POPLINE, MEDLINE via PubMed, and a specialized emergency contraception article database. We also searched reference lists and contacted experts to identify additional published or unpublished trials.

SELECTION CRITERIA: We included randomized controlled trials comparing advance provision and standard access, which was defined as any of the following: counseling which may or may not have included information about emergency contraception, or provision of emergency contraception on request at a clinic or pharmacy.

DATA COLLECTION AND ANALYSIS: We evaluated all identified titles and abstracts found for potential inclusion. Two reviewers independently abstracted data and assessed study quality. We entered and analyzed data using RevMan 4.2.8. We calculated odds ratios with 95% confidence intervals for dichotomous data and weighted mean differences with 95% confidence intervals for continuous data.

MAIN RESULTS: Eight randomized controlled trials met our criteria for inclusion, representing 6389 patients in the United States, China and India. Advance provision did not decrease pregnancy rates (OR 1.0; 95% CI: 0.78 to 1.29 in studies for which we included twelve month follow-up data; OR 0.91; 95% CI: 0.69 to 1.19 in studies for which we included six month follow-up data; OR 0.49; 95% CI: 0.09 to 2.74 in a study with three month follow up data), despite increased use (single use: OR 2.52; 95% CI 1.72 to 3.70; multiple use: OR 4.13; 95% CI 1.77 to 9.63) and faster use (weighted mean difference (WMD) -14.6 hours; 95% CI -16.77 to -12.4 hours). Advance provision did not lead to increased rates of sexually transmitted infections (OR 0.99; 95% CI 0.73 to 1.34), increased frequency of unprotected intercourse, nor changes in contraceptive methods. Women who received emergency contraception in advance were equally as likely to use condoms as other women.

AUTHORS' CONCLUSIONS: Advance provision of emergency contraception did not reduce pregnancy rates when compared to conventional provision. Advance provision does not negatively impact sexual and reproductive health behaviors and outcomes. Women should have easy access to emergency contraception, because it can decrease the chance of pregnancy. However, the interventions tested thus far have not reduced overall pregnancy rates in the populations studied.