Treatment of vaginal bleeding irregularities induced by progestin only contraceptives

Despite their high effectiveness, progestin-only contraceptives are considered less than ideal by the many women who experience disruption of their normal vaginal bleeding pattern when using these methods. Current treatments to control these bleeding irregularities are not sufficiently effective.

We evaluated preventive and therapeutic interventions of bleeding irregularities associated with the use of progestin-only contraceptives.

Literature was identified through database searches, reference lists, organisations and individuals, covering the period until December 2006.

Trials with random or alternate allocation, testing interventions for the prevention or treatment of bleeding irregularities associated with the use of progestin-only contraceptives were eligible.

Results are expressed as relative risks (RR) with 95 % confidence interval (CI) for categorical data and as weighted mean difference (WMD) with 95 % CI for continuous data. When we encountered heterogeneity (visual or statistical) we used the random-effects model (quantitative) or did not produce a summary estimate (qualitative).

19 Randomised controlled trials including 2290 participants were included. Over 60% of these trials had low to moderate risk of bias. Estrogen treatments reduced the number of days of an ongoing bleeding episode in DMPA users and had a positive therapeutic effect in Norplant users. However, treatment frequently led to discontinuation due to gastrointestinal upset. Combinations of oral ethinyl estradiol and levonorgestrel taken by Norplant users experiencing bleeding irregularities, improved bleeding patterns but method discontinuation rates remained the same. Norplant users administered the anti-progestin mifepristone therapeutically reported fewer days of bleeding than those given placebo. Prophylactic oral mifepristone used monthly by new Norplant users reduced bleeding, when compared to placebo.Ibuprofen was reported to decrease the length of bleeding episodes over a year, but the data were not presented in a suitable format for our analysis. Mefenamic acid reduced continued irregular bleeding during treatment in Norplant users, but not among DMPA users. Vitamin E and aspirin had no effect on bleeding patterns in a large trial of women using Norplant. Norplant users receiving tamoxifen had less unacceptable bleeding after treatment and were more likely to continue using Norplant than those receiving placebo.

Some women may benefit from the interventions described, particularly with cessation of an ongoing bleeding episode. Several regimens offer promise in regulating bleeding, but findings need to be reproduced in larger scale trials. Intermittent treatment with an agent may help some women to continue the use of a progestin-only contraceptive. The results of this review do not support routine clinical use of any of the regimens included in the trials, particularly for long-term effect.