Timing luteal support in assisted reproductive technology: a systematic review

Area of Science:

• Reproductive Endocrinology
• Infertility Research
• Clinical Trial Analysis

Background:

• Progesterone (P) supplementation is crucial for luteal phase support in assisted reproductive technology (ART).
• The optimal timing for initiating P supplementation remains a subject of investigation to maximize clinical pregnancy and live birth rates.
• Understanding the impact of P start timing is essential for refining ART protocols.

Purpose of the Study:

• To systematically review and summarize published randomized controlled trial (RCT) data on the timing of progesterone (P) supplementation during the luteal phase in patients undergoing ART.
• To identify optimal P supplementation initiation times to improve outcomes in in vitro fertilization (IVF).

Main Methods:

• Systematic review of published randomized controlled trials (RCTs).
• Included patients undergoing IVF.
• Interventions focused on different starting times of progesterone for luteal support.
• Main outcome measures were clinical pregnancy and live birth rates.

Main Results:

• Five RCTs with 872 patients were identified; a meta-analysis was not feasible due to heterogeneity in P timing, dose, and route.
• Starting P on the day of oocyte retrieval showed 5%-12% higher pregnancy rates compared to before retrieval.
• Initiating P on day 6 post-retrieval resulted in a 16% decrease in pregnancy compared to day 3.
• No significant differences in pregnancy rates were observed when comparing P initiation on the day of oocyte retrieval versus 2 or 3 days after.

Conclusions:

• A potential window for initiating progesterone supplementation exists between the evening of oocyte retrieval and 3 days post-retrieval.
• Current evidence is insufficient to definitively assess the benefits of delaying vaginal progesterone start time to 2 days post-retrieval.
• Further high-quality randomized clinical trials are necessary to establish the optimal timing for progesterone start in ART luteal support.