Evidence-based family planning: the paradigm for the third millennium

Cochrane systematic reviews of IUD trials: lessons learned

BACKGROUND

Intrauterine devices (IUDs) are the most widely used reversible contraceptives in the world today, and decisions about their use should reflect the best available evidence.

STUDY DESIGN

We performed a computer search of the Cochrane Library for all IUD-related reviews.

RESULTS

Eleven reviews related to IUDs have been registered in The Cochrane Library; 10 have been completed, and one is in progress. Topics include type of IUD, timing of insertion, clinical management, emergency contraception and use as gynecological treatment. The copper T380A is the most effective copper IUD; the levonorgestrel intrauterine system has efficacy comparable to that of IUDs with >250 mm(2) of copper. The frameless device may be comparable in efficacy to the copper T380A, although whether problems with the initial inserter are resolved is unclear. Immediate postpartum and postabortal insertion appears safe and effective, although trials comparing immediate to delayed insertions are scarce. Prophylactic antibiotics at the time of insertion appear unwarranted except in populations with a high prevalence of sexually transmitted diseases. Many nonsteroidal anti-inflammatory drugs reduce pain and bleeding associated with IUDs, although prophylactic use of ibuprofen does not improve continuation rates. The levonorgestrel system is superior to oral progestins in treating heavy uterine bleeding. This IUD compares favorably with endometrial ablation techniques and presents an alternative to hysterectomy for many women.

DISCUSSION

Trials are needed to evaluate immediate vs. delayed insertion after delivery or abortion and to explore emerging therapeutic uses of the levonorgestrel system, such as treatment of endometrial hyperplasia.

The Cochrane Fertility Regulation Group: synthesizing the best evidence about family planning

The Fertility Regulation Group of the Cochrane Collaboration has been assessing the best available evidence on fertility regulation, family size and birth spacing. By the end of 2005, this group had published 32 systematic reviews and 12 protocols; most reviews were on contraception. Because of suboptimal trial quality, firm conclusions could be made in only five reviews. Threats to internal validity in published trials include the absence of description of allocation concealment, intentional exclusion of participants after randomization, failure to use intention-to-treat analyses and lack of treatment blinding. The precision of results has been limited by small sample sizes. The finding that most trials of oral contraceptives were conducted by pharmaceutical companies raises concerns about potential commercial bias. Of necessity, most information about fertility regulation effectiveness and adverse effects comes from observational studies, which vary widely in quality. Systematic reviews of evidence, with an emphasis on randomized controlled trials when available, will continue to improve fertility regulation in the years ahead.