| This study is focused in appraising the current evidence comparing double and single IUI for achieving a
pregnancy. The primary outcomes were live birth and ectopic pregnancy per women randomized.
Secondary outcomes included clinical pregnancy and miscarriage. The evaluation of the risk of bias
within each study was structured using the Cochrane risk of bias and the overall quality of the body of
evidence was assessed through the GRADE criteria. Electronic searches were run in 4 databases and
resulted in 15 studies included encompassing 3795 women. The subgroup ‘mild male infertility’ included
1246 women whilst the subgroup ‘normal semen quality’ included 1188 women. Clinical pregnancy was
reported by all studies, and there is no evidence of a difference between single and double IUI (RR 1.22, CI
0.97 to 1.54, 15 RCTs, 3795 women, I2 = 45%). In the subgroup analysis, we could not identify a particular
group that could benefit from the intervention. No conclusion can be drawn regarding live birth, ectopic
pregnancy, and miscarriage because they were reported by too few studies and the estimates were too
imprecise. Currently, there is no evidence to support the use of double IUI in clinical practice. It requires a
second appointment and insemination, thus making the treatment more complex and expensive,
without a clear evidence of a benefit. Nevertheless, evidence is still of low quality and our confidence in
the effect estimate is limited: the true effect may be substantially different from the hereby
demonstrated. |