Follicular and luteal phase endometrial thickness and echogenic pattern and pregnancy outcome in oocyte donation cycles

To study the effect of endometrial thickness (ET) and echogenic pattern (EP) in oocyte donation cycles upon pregnancy outcomes. Seventy-nine cycles resulting in blastocyst embryo transfer were evaluated. Donors underwent ovarian hyperstimulation using rFSH and GnRH-antagonist. Recipients were synchronized to donors using GnRH-agonist down-regulation followed by fixed dose of estrogen (E2) and progesterone (P4) following hCG. Transvaginal ultrasound (US) obtained ET and EP 10-11 days after initiation of E2 and on day of embryo transfer. Primary outcome was ET and EP in pregnant and non-pregnant cycles. Stimulation and embryology data was analyzed in donors to assess differences prior to transfer. Fifty-nine cycles resulted in clinical pregnancy. No differences were observed in pregnant vs. non-pregnant cycles in proliferative or secretory ET and EP. Similar baseline and stimulation characteristics were found in pregnant and non-pregnant cycles. Regression analysis showed end thickness were not predictive of pregnancy outcomes. Endometrial characteristics in recipients prior to and following progesterone were not predictive of pregnancy outcomes.