Background: Progress in vitrification techniques has allowed reproductive physicians to consider new strategies for using progestin as an alternative to a GnRH analogue to improve in vitro fertilisation (IVF). However, the role of progestin in blocking luteinising hormone (LH) surges and its potential in clinical practice are unclear, especially for poor responders. We designed a prospective randomised controlled trial (RCT) to compare the efficacy of a gonadotropin-releasing hormone (GnRH) antagonist and progestin in blocking LH surges and premature ovulation in poor responders.
Methods/design: Poor responders who meet the Bologna criteria will be randomised to one of two stimulation regimens-gonadotropin-releasing hormone (GnRH) antagonist or progestin-primed ovarian stimulation (PPOS)-using a computer-generated random number. Fresh embryos were transferred in the GnRH antagonist group and frozen embryos were transferred in the PPOS group. The primary outcome is the incidence of premature LH surges. Secondary outcomes include the number of oocytes retrieved, the number of embryos available for transfer, implantation rates and clinical pregnancy. The sample size for this trial is estimated as 340 participants, with 170 participants in each group. The data analysis will be by intention to treat.
Discussion: To our knowledge, this is the first RCT to examine the efficacy of administering progestin orally to block LH surges and premature ovulation compared with the GnRH antagonist protocols in poor responders undergoing IVF treatment.
Trial registration: www.chictr.org.cn . ChiCTR-IPR-17010906 . Registered on 18 March 2017.
Keywords: GnRH antagonist; LH surge; Poor responders; Progestin.