"Reverse" Dual Stimulation Has Comparable Efficacy, but Higher Efficiency, than Two Conventional Follicular Phase...

Area of Science:

• Reproductive Endocrinology
• Infertility Treatment

Background:

• Dual stimulation in controlled ovarian stimulation (COS) yields more oocytes but precludes fresh embryo transfer (ET).
• Reverse-dual stimulation (R-DS) aims to enable fresh ET by altering the stimulation sequence.
• This study compares R-DS with two consecutive follicular-phase COS (2FP-COS) cycles.

Purpose of the Study:

• To investigate the reproductive outcomes of R-DS compared to 2FP-COS in poor responders.
• To assess if R-DS can reduce the time to pregnancy.

Main Methods:

• Retrospective study of 146 poor responders (45 R-DS, 101 2FP-COS).
• R-DS involved a first COS 5 days post-ovulation and a second 5 days post-oocyte retrieval.
• Primary outcome was time to pregnancy; secondary outcomes included oocyte retrieval and live birth rates.

Main Results:

• R-DS showed comparable stimulation length, oocyte retrieval, and blastocyst formation to follicular phase COS.
• Progesterone levels remained <1.0 ng/mL at ovulation trigger in R-DS.
• R-DS resulted in a significantly shorter time to pregnancy (52.9 days) versus 2FP-COS (103.2 days).

Conclusions:

• R-DS is non-inferior to 2FP-COS for oocyte retrieval and cumulative live birth rates.
• R-DS facilitates immediate fresh embryo transfer.
• R-DS significantly reduces time to pregnancy, a key benefit for poor responders.