Reproductive biomedicine online | 2019
Live birth rates with a freeze-only strategy versus fresh embryo transfer: secondary analysis of a randomized clinical trial.
Abstract
RESEARCH QUESTION\nWhat are the roles of serum progesterone and endometrial thickness as biomarkers in the decision between a freeze-only and fresh embryo transfer in IVF for women without polycystic ovary syndrome (PCOS)?\n\n\nDESIGN\nThis was a secondary analysis of a randomized controlled trial including 782 couples who were followed up until the end of the first completed cycle. Couples scheduled for their first or second IVF cycle with a FSH/gonadotrophin-releasing hormone antagonist protocol were randomized to a freeze-only (n\u202f=\u202f391) or fresh embryo transfer (n\u202f=\u202f391) strategy. The endpoint for this analysis was live birth rate (LBR) after the first embryo transfer.\n\n\nRESULTS\nThere was no significant difference in LBR after the first cycle between a freeze-only and fresh transfer strategy. When serum progesterone levels at trigger were in the third quartile (Q3, 1.14-1.53\xa0ng/ml), LBR was significantly higher in the freeze-only versus fresh transfer group (P\u202f=\u202f0.01); when serum progesterone was ≥1.14\xa0ng/ml, LBR was significantly better in the freeze-only group (37.4% versus 23.8% in the fresh transfer group; P\u202f=\u202f0.004). LBRs in the freeze-only and fresh embryo transfer groups were similar across all quartiles of endometrial thickness, although a small advantage for freeze-only in women with a very thin endometrium could not be excluded.\n\n\nCONCLUSIONS\nSerum progesterone level on the day of trigger may have potential as a biomarker on which to base a prospective decision about whether to use a freeze-only or fresh embryo transfer strategy in women undergoing IVF.