Comparing Letrozole-Stimulated and Artificial Cycle Strategies for Preparing the Uterus in Women with Irregular Menstrual Cycles Undergoing Frozen Embryo Transfer

What this Trial Is About

Researchers are evaluating two different methods of preparing the uterus lining for frozen embryo transfer in women with irregular menstrual cycles. This randomized clinical trial aims to compare the letrozole-stimulated cycle strategy with the artificial cycle strategy to see which method results in a higher live birth rate after one cycle of preparation. The study focuses on women who have irregular periods and are undergoing assisted reproduction technology using frozen embryos. Participants will be randomly assigned to one of two groups. The letrozole-stimulated cycle group will take letrozole for 5 days early in their menstrual cycle, followed by monitoring follicle growth, ovulation induction if needed, and support with vaginal progesterone. The artificial cycle group will take oral estradiol valerate for about 10 days starting early in the cycle, followed by vaginal progesterone support. Both groups will have embryo transfer 5 days after starting progesterone and continue hormonal support until the 12th week of pregnancy. The study will also track if any cycles are canceled due to certain criteria. During the study, participants will have ultrasounds to monitor follicle growth or endometrial thickness and hormone levels. Researchers will measure outcomes including live birth rates, pregnancy tests, implantation rates, miscarriage rates, birth outcomes, and safety events. The total participation includes one cycle of endometrial preparation and follow-up through pregnancy to assess the primary outcome at 22 weeks gestational age. Additional pregnancy and birth-related outcomes will also be recorded.

Letrozole-stimulated Cycle Strategy Versus Artificial Cycle Strategy (LETSACT)