The safety of intrauterine devices among young women: a systematic review.

OBJECTIVE: The objective was to determine the association between use of intrauterine devices (IUDs) by young women and risk of adverse outcomes.

METHODS: We searched Pubmed, CINAHL, Embase, Popline and the Cochrane Library for articles from inception of database through December 2015. For outcomes specific to IUD use (IUD expulsion and perforation), we examined effect measures for IUD users generally aged 25 years or younger compared with older IUD users. For outcomes of pregnancy, infection, pelvic inflammatory disease (PID), and heavy bleeding or anemia, we examined young IUD users compared with young users of other contraceptive methods or no method.

RESULTS: We identified 3169 articles of which 16 articles from 14 studies met our inclusion criteria. Six studies (Level II-2, good to poor) reported increased risk of expulsion among younger age groups compared with older age groups using copper-bearing (Cu-) IUDs. Two studies (Level II-2, fair) examined risks of expulsion among younger compared with older women using levonorgestrel-releasing (LNG-) IUDs; one reported no difference in expulsion, while the other reported increased odds for younger women. Four studies (Level II-2, good to poor) examined risk of expulsion among Cu- and LNG-IUD users combined and reported no significant differences between younger and older women. For perforation, four studies (Level II-2, fair to poor) found very low perforation rates (range, 0%-0.1%), with no significant differences between younger and older women. Pregnancies were generally rare among young IUD users in nine studies (Level I to II-2, fair to poor), and no differences were reported for young IUD users compared with young combined oral contraceptive (COC) or etonogestrel (ENG) implant users. PID was rare among young IUD users; one study reported no cases among COC or IUD users, and one reported no difference in PID among LNG-IUD users compared with ENG implant users from nationwide insurance claims data (Level I to II-2, fair). One study reported decreased odds of bleeding with LNG-IUD compared with COC use among young women, while one study of young women reported decreased odds of removal for bleeding with LNG-IUD compared with ENG implant (Level I to II-2, fair).

CONCLUSION: Overall evidence suggests that the risk of adverse outcomes related to pregnancy, perforation, infection, heavy bleeding or removals for bleeding among young IUD users is low and may not be clinically meaningful. However, the risk of expulsion, especially for Cu-IUDs, is higher for younger women compared with older women. If IUD expulsion occurs, a young woman is exposed to an increased risk of unintended pregnancy if replacement contraception is not initiated. IUDs are safe for young women and provide highly effective reversible contraception.