The efficacy of intrauterine devices for emergency contraception: a systematic review of 35 years of experience

When can a woman have an intrauterine device inserted? A systematic review

BACKGROUND

Intrauterine device (IUD) insertion during menses may be viewed as preferable by some providers, as it provides reassurance that the woman is not pregnant. However, this practice may result in unnecessary inconvenience and cost to women. The objective of this systematic review is to evaluate the evidence for the effect of inserting IUDs on different days of the menstrual cycle on contraceptive continuation, effectiveness and safety.

STUDY DESIGN

We searched the MEDLINE database for peer-reviewed articles published in any language from database inception through March 2012 concerning the effect of inserting copper IUDs (Cu-IUD) or levonorgestrel-releasing IUDs (LNG-IUDs) on different days of the menstrual cycle on contraceptive continuation, effectiveness, and safety. The quality of each individual piece of evidence was assessed using the United States Preventive Services Task Force grading system.

RESULTS

We identified eight articles that met the criteria for review. Each study examined the Cu-IUD; no studies were identified that examined the LNG-IUD. Overall, these studies suggest that timing of Cu-IUD insertion has little effect on longer term outcomes (rates of continuation, removal, expulsion, or pregnancy) or on shorter term outcomes (pain at insertion, bleeding at insertion, immediate expulsion). Specifically, there was no evidence to suggest that outcomes were better when Cu-IUD insertions were performed during menses. Limitations of the studies include small sample sizes for insertions performed during later days of the menstrual cycle and non-randomized assignment to timing of insertion.

CONCLUSIONS

There is fair evidence (body of evidence grading: II-2, fair) indicating that timing of Cu-IUD insertion has little effect on contraceptive continuation, effectiveness or safety.

Results from pooled Phase III studies of ulipristal acetate for emergency contraception

BACKGROUND

Ulipristal acetate (UPA) is a new effective option to prevent unintended pregnancies up to 5 days after unprotected intercourse. We used pooled data from two Phase III studies to refine our understanding of the efficacy of UPA by time from unprotected intercourse and the effects of other factors on pregnancy rates.

STUDY DESIGN

Data from two Phase III studies were pooled to create a larger analysis population. Analyses were performed on the first participation of 2183 women.

RESULTS

A total of 41 women became pregnant despite the use of UPA, yielding an overall proportion pregnant of 1.9% (1.3%-2.5%). Proportions of pregnant women were higher among those with further acts of unprotected intercourse in the same cycle and among obese women. These varied from 1.3% (0.9%-2.0%) among nonobese women who had no further acts of unprotected intercourse (n=1704) to 8.3% (0.2%-38.5%) among obese women who had subsequent unprotected intercourse (n=12).

CONCLUSIONS

UPA is effective and safe in preventing pregnancy after unprotected intercourse. Its effectiveness is lower among women who have subsequent unprotected intercourse and among obese women.