Work

Urine Progesterone Level as a Diagnostics Tool to Evaluate the Need for Luteal Phase Rescue in Hormone Replacement Therapy Frozen Embryo Transfer Cycles

Year: 2025

Type: article

Abstract: Additional progesterone administration during the luteal phase enhances reproductive outcomes in Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) cycles in patients with low serum progesterone (P4). In this study we wanted to explore the use of urine P4 as a diagnostic tool during the luteal phase. This prospective observational cohort included a total of 464 HRT-FET cycles. The protocol entailed oral oestradiol (6 mg/24 h), followed by vaginal micronised progesterone (400 mg/12 h). On the day of blastocyst transfer, urine and serum samples were collected. Urine samples were analysed using an ARCHITECT automated immunoassay. A significant difference was found in median urine P4 between patients with serum P4 higher or lower than 11 ng/mL: 6400 ng/mL IQR [2528; 11,930] vs. 3408 ng/mL IQR [592; 6688], p < 0.001. The optimal cut-off to achieve live birth was a urine P4 ≥ 4000 ng/mL. The live birth rate was significantly higher in patients with urine P4 ≥ 4000 ng/mL, 48% (107/222) vs. 35% (45/130), respectively (p = 0.013). The odds ratio for live birth was 1.8 in patients with urine P4 ≥ 4000 ng/mL, 95% CI [1.067; 3.018], p = 0.028. The findings of the present study suggest that urine progesterone could be a valuable diagnostic tool to evaluate the need for additional progesterone in HRT-FET cycles.

Source: International Journal of Molecular Sciences

DOI: 10.3390/ijms262110795