Effects of short-acting GnRHa on pregnancy outcome in frozen-thawed embryo transfer cycles

Abstract

Objective To investigate the effect of short-acting gonadotrophin releasing hormone agonist (GnRHa) on pregnancy outcome in frozen-thawed embryo transfer (FET). Methods The retrospective analysis was based on 838 FET cycles including 210 natural cycles and 628 hormone replacement cycles. According to whether use GnRHa after transfer as luteal phase support, these cycles were divided into natural cycles with GnRHa group (n=72), natural cycles without GnRHa group (n=138), hormone replacement cycles with GnRHa group (n=111), and hormone replacement cycles without GnRHa group (n=517). The clinical pregnancy outcomes were compared between natural cycles with GnRHa group and natural cycles without GnRHa group, hormone replacement cycles group and hormone replacement cycles without GnRHa group respectively. Results In natural cycles with GnRHa group, the pregnancy rate (61.11%) and implantation rate (40.85%) were significantly higher than those in natural cycles without GnRHa group (44.93%, 30.26%). But in hormone replacement cycles, the use of GnRHa as luteal phase support did not improve the pregnancy outcome. Conclusions Administration of GnRHa can increase clinical and implantation rates in natural frozen-thawed embryo transfer cycles. But it is useless in the hormone replacement cycles. Key words: Gonadotrophin releasing hormone agonist; Frozen-embryo transfer; Luteal phase support