IUD for EC
Dr. Linan Cheng
Shanghai Institute of Family Planning Technical Instruction, The International Peace
Maternity and Child Health Hospital, China Welfare Institute, Shanghai, PR China
Emergency contraception is defined as the use of a drug or device as an emergency
measure to prevent pregnancy after unprotected intercourse. From this definition it follows
that methods of emergency contraception are used after coitus but before pregnancy
occurs, and that they are intended as a back up for occasional use rather than a regular
form of contraception.
The first report by Lippes in 1976 indicated an effectiveness of >95% within 5 days of
unprotected intercourse. Askallani 1987 first compared Cu-IUD (Cu-T 200) insertion with
expectant management in women requesting emergency contraception within 4 days of
unprotected intercourse. There was a significantly higher number of pregnancies in the
expectant management group (RR: 0.09, 95% CI 0.03 to 0.26). The comparative
effectiveness of inserting an intra-uterine device has not been adequately investigated.
Whereas it might be difficult to conduct randomized controlled trials of intra-uterine devices
with other interventions with the woman as unit of randomization, cluster randomization
might overcome this problem. Although there are many barriers to using intra-uterine
devices for emergency contraception, data from nonrandomized studies that were all
conducted in China suggest that inserting Copper-IUDs for emergency contraception could
be effective in preventing unintended pregnancy (3 pregnancies/1470 women, failure rate:
0.20%). These findings are in line with the findings of the Askalani trial that compared IUD
insertion with nothing. In the review of the efficacy of the IUD used in emergency
contraception by Trussell and Ellertson a meta-analysis of 20 published papers of post-
coital IUDs showed a failure rate of 0.1%from more than 8400 insertions.
The postcoital insertion of an IUD is an option that can be used up to 5 days after the
estimated time of ovulation and can be left in the uterus as a long-term regular
Methods – What’s new?
Linan Cheng (China)
Background. Emergency contraception is using a drug or copper intrauterine device (Cu-IUD) to prevent pregnancy shortly after unprotected intercourse. Several interventions are available for emergency contraception. Information on the comparative efficacy, safety and convenience of these methods is crucial for reproductive health care providers and the women they serve.
Objectives. To determine which emergency contraceptive method following unprotected intercourse is the most effective, safe and convenient to prevent pregnancy.
Selection criteria. Randomised controlled trials and controlled clinical trials including women attending services for emergency contraception following a single act of unprotected intercourse were eligible.
Data collection & analysis. Data on outcomes and trial characteristics were extracted in duplicate and independently by two reviewers. Quality assessment was also done by two reviewers independently. Meta-analysis results are expressed as relative risk (RR) using a fixed-effects model with 95% confidence interval (CI). In the presence of statistically significant heterogeneity a random-effect model was applied.
Main results. Eighty trials with 43,743 women were included. Most trials were conducted in China (70/81). There were more pregnancies with levonorgestrel compared to mid-dose (25-50 mg) (15 trials, RR: 2.01; 95% CI: 1.27 to 3.17) or low-dose mifepristone (<25 mg) (9 trials, RR: 1.43; 95% CI: 1.02 to 2.01). Low-dose mifepristone was less effective than mid-dose (20 trials, RR:0.67; 95% CI: 0.49 to 0.92), but this effect was no longer statistically significant when only high quality trials were considered (6 trials, RR: 0.75; 95% CI: 0.50 to 1.10). Single dose levonorgestrel (1.5 mg) administration seemed to have similar effectiveness as the standard 12 hours apart split-dose (0.75 mg twice) (2 trials, 3830 women; RR: 0.77, 95% CI: 0.45 to 1.30). Levonorgestrel was more effective than the Yuzpe regimen in preventing pregnancy (2 trials, RR: 0.51; 95% CI: 0.31 to 0.83). CDB-2914 (a second-generation progesterone receptor modulator) may be as effective as levonorgestrel (1 trial, 1549 women; RR:1.89; 95% CI: 0.75 to 4.64) but the confidence interval is wide and the result compatible with higher or lower effectiveness. Delay in the onset of subsequent menses was the main unwanted effect of mifepristone and seemed to be dose-related.
Reviewers' conclusions. Mifepristone middle dose (25-50 mg) was superior to other hormonal regimens. Mifepristone low dose (<25 mg) could be more effective than levonorgestrel 0.75 mg (two doses) but this was not conclusive. Levonorgestrel proved more effective than the Yuzpe regimen. The copper IUD was another effective emergency contraceptive that can provide ongoing contraception.