Intrauterine injection of human chorionic gonadotropin before embryo transfer can improve in vitro fertilization-embryo transfer outcomes: a meta-analysis of randomized controlled trials.

OBJECTIVE: To evaluate whether intrauterine injection of hCG before embryo transfer can improve IVF-ET outcomes.

DESIGN: Meta-analysis.

SETTING: Not applicable.

PATIENT(S): Infertile women who underwent IVF-ET and received an intrauterine injection of hCG before ET.

INTERVENTION(S): Infertile women treated with or without intrauterine hCG injection before ET.

MAIN OUTCOME MEASURE(S): The primary outcomes were live birth rate (LBR), ongoing pregnancy rate (OPR), and clinical pregnancy rate (CPR), and the secondary outcomes were implantation rate (IR) and miscarriage rate (MR). Odds ratios with 95% confidence intervals (CIs) and successful ET rates were pooled to determine the effects of hCG on IVF-ET outcomes.

RESULT(S): Fifteen randomized controlled trials (RCTs) with a total of 2,763 participants were included. Infertile women in the experimental group (treated with intrauterine hCG injection before ET) exhibited significantly higher LBR (44.89% vs. 29.76%), OPR (48.09% vs. 33.42%), CPR (47.80% vs. 32.78%), and IR (31.64% vs. 22.52%) than those in the control group (intrauterine injection of placebo or no injection). Furthermore, MR was significantly lower (12.45% vs. 18.56%) in the experimental group than in the control group.

CONCLUSION(S): The findings of this meta-analysis indicate that intrauterine injection of hCG can improve LBR, OPR, CPR, and IR after IVF-ET cycles. In addition, different timing and dosages of hCG administration may exert different effects on IVT-ET outcomes. Notably, infertile women treated with 500 IU hCG within 15 minutes before ET can achieve optimal IVF-ET outcomes.