The benefit of human chorionic gonadotropin supplementation throughout the secretory phase of frozen-thawed embryo transfer cycles

Objective

To assess whether supplementation with hCG throughout the secretory phase of hormonally modulated cycles of frozen-thawed embryos might positively affect the outcome of such cycles.

Design

Prospective, randomized controlled trial.

Setting

University teaching hospital.

Patient(s)

Patients undergoing frozen-thawed embryo transfer cycles.

Intervention(s)

Patients were randomly divided into two groups by the last digit of their identification number. Group A received our standard protocol for endometrial preparation, whereas group B patients were given an additional 250 μg of recombinant hCG on day of P initiation, the day of embryo transfer, and 6 days later. Throughout the cycle, and to compare between the groups, serial ultrasound examinations and hormonal tests of E₂ and P serum levels were obtained.

Main Outcome Measure(s)

Implantation and clinical pregnancy rates (PR).

Result(s)

One hundred sixty-five patients were enrolled in this study, 78 in the control group and 87 in the hCG-treated group. Progesterone levels and endometrial thickness were similar throughout the cycle in both groups. The E₂ level was significantly higher in group B on the day of embryo transfer and 6 days later. The PRs did not differ between the two groups (28.2% and 32.2% for groups A and B, respectively). Similarly, the implantation rates were comparable between the groups (12.7% and 14.9%, respectively).

Conclusion(s)

No advantage was found concerning PR and implantation rate by supplementing the secretory phase with hCG in patients undergoing transfer of frozen-thawed embryo in hormonally modulated cycles.

Key Words: hCG, frozen-thawed embryo transfer, implantation