What is the preferred method for timing natural cycle frozen-thawed embryo transfer?

Area of Science:

• Reproductive Endocrinology
• Assisted Reproductive Technologies

Background:

• Natural cycles (NC) offer efficient endometrial-embryo synchronization for frozen embryo transfer (FET).
• Timing ovulation is crucial for successful FET in natural cycles.

Purpose of the Study:

• To compare the efficacy of human chorionic gonadotrophin (HCG) ovulation triggering versus spontaneous ovulation detection for timing FET in natural cycles.
• To evaluate the impact of HCG triggering on cycle monitoring frequency and outcomes.

Main Methods:

• Retrospective study of 132 natural cycle frozen embryo transfer (NC-FET) cycles in 112 women.
• Group A: FET timed with HCG ovulation trigger (n=61).
• Group B: FET timed with detected spontaneous ovulation (n=71).

Main Results:

• The number of monitoring visits was significantly lower in the HCG-triggered group (3.46 ± 1.8) compared to the spontaneous ovulation group (4.35 ± 1.4) (P < 0.0001).
• Demographic, reproductive, and cycle characteristics were comparable between groups.
• Pregnancy and delivery rates were similar in both groups.

Conclusions:

• Ovulation triggering with HCG in natural cycles significantly reduces the need for monitoring visits.
• HCG triggering improves patient convenience and cost-effectiveness for NC-FET.
• This strategy does not adversely affect clinical outcomes such as pregnancy and delivery rates.