A Cochrane review included 15 studies; of 4 with full reports, 3 were small trials. Newer trials compared immediate postplacental insertion versus early (10 minutes to 48 hours) or standard insertion (during the postpartum visit). A study (n=102) compared immediate (within 10 minutes of passing the placenta) and delayed (6 to 8 weeks post-partum) insertion of levonorgestrel-releasing intrauterine system (IUS); expulsion by 6 months was more likely for the immediate group than the delayed insertion group (23.5% vs 4.4%, OR 6.77, 95% CI 1.43 to 32.14). Insertion rates did not differ significantly between study arms. In the meta-analysis, IUD use at 6 months was more likely with immediate insertion than with standard insertion (OR 2.04, 95% CI 1.01 to 4.09; 4 trials, n=243), though expulsion by 6 months was more likely for the immediate group, but the confidence interval was wide (OR 4.89, 95% CI 1.47 to 16.32; 4 trials, n= 210). Study arms did not differ in use at 3 or 12 months in individual small trials.
The other 8 studies were 15 to 30 years old and examined immediate insertion alone. In these studies, modifications of existing devices, such as adding absorbable sutures or additional appendages, did not appear beneficial. Most studies showed no important differences between insertions done by hand or by instruments. Lippes Loop and Progestasert devices did not perform as well as did copper devices.Comment: The quality of evidence is downgraded by study quality (unclear allocation concealment), and by imprecise results (few patients and wide confidence intervals).