Hormonal and intrauterine methods for contraception for women aged 25 years and younger.

BACKGROUND: Women between the ages of 15 and 24 years have high rates of unintended pregnancy; over half of women in this age group want to avoid pregnancy. However, women under age 25 years have been found to have higher typical contraceptive failure rates within the first 12 months of use than older women. High discontinuation rates may also be a problem in this population. Concern that adolescents and young women will not find hormonal or intrauterine contraceptives acceptable or effective might deter healthcare providers from recommending these contraceptive methods. 

OBJECTIVES: This review examined randomized controlled trials of hormonal or intrauterine methods used for contraception in women aged 25 years and younger.

SEARCH METHODS: In February 2012, we searched the computerized databases Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, POPLINE, CINAHL, and LILACS for randomized controlled trials that compared hormonal or intrauterine methods used for contraception in women aged 25 years and younger. We also searched for current trials via ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (ICTRP).

SELECTION CRITERIA: We considered all randomized controlled trials in any language that reported the contraceptive failure rates for hormonal or intrauterine contraceptive methods, when compared to another contraceptive method, for women aged 25 years and younger. The other contraceptive method could be another intrauterine method, another hormonal method, or a non-hormonal method. Treatment duration must have been at least three months.

DATA COLLECTION AND ANALYSIS: The first author extracted the data and entered the information into RevMan. Another author performed an independent data extraction and verified the initial entry. Because of disparate contraceptive exposures, we were not able to combine the studies in meta-analysis.

MAIN RESULTS: Four trials met the inclusion criteria. The trials compared the combined oral contraceptive versus the transdermal contraceptive patch, the combined oral contraceptive versus the vaginal contraceptive ring, the combined oral contraceptive versus the levonorgestrel intrauterine system, and the levonorgestrel intrauterine system versus the copper T380A intrauterine device. Because of small numbers of participants, the trials were not informative regarding contraceptive efficacy. Data on continuation rates were also limited. In one of these trials, the levonorgestrel intrauterine system was found to have a similar 12-month continuation rate as the combined oral contraceptive (odds ratio (OR) 1.48; 95% CI 0.76 to 2.89). In that trial, a higher proportion of women discontinued the levonorgestrel intrauterine system because of pain (OR 14.62; 95% CI 0.81 to 263.16), whereas a higher proportion of women discontinued the combined oral contraceptive for personal reasons (OR 0.27; 95% CI 0.09 to 0.85).

AUTHORS' CONCLUSIONS: Current evidence is insufficient to compare contraceptive efficacy and continuation rates for hormonal and intrauterine methods in women aged 25 years and younger. Limited data suggests that the levonorgestrel intrauterine system may be an acceptable alternative to the combined oral contraceptive in this population.