P–649 Should women receive luteal support following natural cycle frozen embryo transfer? A systematic review and meta-analysis

Abstract

Abstract Study question Should women receive luteal phase support (LPS) following natural cycle frozen embryo transfer (NC-FET)? Summary answer Progesterone LPS following NC-FET increases the live birth rate. There is no evidence to support the administration of hCG for LPS in these cases. What is known already Whether or not women should receive LPS following NC-FET is highly controversial. Previous studies have shown conflicting results. Study design, size, duration We conducted a systematic search of the literature published in Medline/PubMed, Embase and the Cochrane Library, from January 2000 until December 2020. We included all original English, peer-reviewed articles, irrespective of study-design. The search strategy included keywords related to natural cycle frozen embryo transfer and luteal phase support. Studies reporting the results of artificial or stimulated FET cycles were excluded. Participants/materials, setting, methods Our systematic search generated 395 records. After screening, eight studies were included in the review and seven studies were included in the meta-analysis. Two studies (n = 858) used hCG, and 6 studies (n = 1507) used progesterone for luteal support. Four studies were randomized controlled trials (RCTs), whereas the other four were historic cohort studies. Main results and the role of chance In a meta-analysis using random effects model, hCG administration for LPS did not increase the clinical pregnancy rate (two studies, OR 0.85, 95% CI 0.64–1.14). On the other hand, progesterone LPS was associated with a higher clinical pregnancy rate (five studies, OR 1.48, 95% CI 1.14–1.94), and a higher live birth rate (three studies, OR 1.67, 95% CI 1.19–2.36). Limitations, reasons for caution There was large heterogeneity in progesterone dose and route of administration, as well as the methods used for ovulation detection and triggering. Moreover, only four studies were randomized. Finally, both studies examining the use of hCG for LPS were performed by the same group of researchers in a single center. Wider implications of the findings: The available evidence indicates that progesterone administration for LPS is beneficial following natural cycle frozen embryo transfer. There is no evidence to support the administration of hCG for LPS in these cases. Additional Large RCTs are necessary in order to improve the quality of evidence and validate our findings. Trial registration number PROSPERO ID: CRD42020199045