Intrauterine injection of HCG before embryo transfer: a parallel, double-blind randomized trial

Area of Science:

• Reproductive Endocrinology
• In Vitro Fertilization (IVF)

Background:

• The efficacy of intrauterine human chorionic gonadotropin (HCG) administration prior to embryo transfer in improving in vitro fertilization (IVF) outcomes remains a subject of investigation.
• Optimizing implantation and live birth rates in IVF cycles is a primary goal in assisted reproductive technologies.

Purpose of the Study:

• To evaluate whether intrauterine administration of HCG before embryo transfer enhances the live birth rate in women undergoing IVF cycles.
• To assess the impact of HCG on clinical and ongoing pregnancy rates as secondary outcomes.

Main Methods:

• A parallel, randomized controlled trial involving 181 infertile women undergoing embryo transfer after IVF.
• Participants were randomized (1:1) to receive either intrauterine HCG (500 IU) or a placebo (culture media) 4 minutes before embryo transfer.
• The primary outcome was live birth rate, analyzed using the intention-to-treat principle.

Main Results:

• Live birth rates were 24% in the HCG group versus 19% in the control group (Relative Risk [RR] 1.29, 95% Confidence Interval [CI] 0.74-2.27), a difference that was not statistically significant.
• Clinical pregnancy rates were 34% (HCG) vs. 26% (control) (RR 1.31, 95% CI 0.84-2.04), and ongoing pregnancy rates were 24% vs. 19% (RR 1.29, 95% CI 0.74-2.27).
• Treatment outcomes in the control group were lower than anticipated.

Conclusions:

• Intrauterine HCG administration before embryo transfer did not demonstrate a significant improvement in live birth rates for women undergoing IVF.
• The study was powered to detect a 20% difference, thus a smaller, clinically significant difference cannot be definitively excluded.
• Further investigation may be warranted to explore potential benefits in specific patient populations or with modified protocols.