Luteal support for 144 hours: a new discovery on the golden window to improve IVF success rate
In the field of assisted reproduction, we have long focused on embryo quality and uterine environment, but overlooked another determining factor – the temporal precision of luteal support.2025 A study by Nishio’s team at Fujita University of Health in Japan, published in Cureus, unveiled the startling discovery that, during a frozen embryo transfer cycle, the clinical pregnancy rate jumped dramatically with oral The study, published in Cureus in 2025 by Nishio’s team at Fujita Health University in Japan, uncovered the startling finding that oral administration of dexamethasone for ≥144 hours (6 days) in frozen embryo transfer cycles was associated with a significant jump in the clinical pregnancy rate, especially in non-quality embryos.2 This finding overturned the conventional wisdom that the longer the luteal support, the better, and provided new hope for families with recurrent transfer failures. 🔬 I. Implantation Window: The “Golden 72 Hours” for Embryo Landing Precise timing of the endometrium Embryo implantation is not possible at any time, but needs to be accomplished during a specific time period – the Window of Implantation (WOI). In most women, the WOI occurs 19-22 days after ovulation and lasts only 12-24 hours.2 It’s like a high-class hotel that opens its doors to VIPs for only a short period of time, and if you miss it, you won’t be able to check in. Synchronization Makes the Difference Even with high-quality embryos screened by PGT-A, the pregnancy rate after transfer is still only 54.4%. According to Dr. Michael Evans of the Johns Hopkins Fertility Center, “30% of failures stem from unsynchronized development of the embryo and the endometrium. It’s like scattering top quality seeds in untilled or sloughed off soil; even the highest quality will have a hard time germinating.” ⏳ II. The 144-hour rule: a precision revolution in luteal support Key study…
