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Impact of gonadotropin type on progesterone elevation during ovarian stimulation in GnRH antagonist cycles
B Lawrenz1, F Beligotti2, N Engelmann3
1IVI Middle East, Fertility Clinic, Royal Marina Village, Villa B 22-23, Abu Dhabi, UAE barbara.lawrenz@ivivf.com.
Study Question:
Does hormonal stimulation with corifollitropin alpha (CFA) only, mimicking a step down protocol, result in lower incidence of progesterone elevation on the day of hCGtrigger as compared to sustained stimulation with recombinant FSH (rFSH)?
Summary Answer:
The current findings support the concept that sustained FSH stimulus contributes to premature progesterone elevation in stimulated IVF cycles.
What Is Known Already:
Serum progesterone rise during the follicular phase of ovarian stimulation for IVF treatment seems to be related to a poorer reproductive outcome. However, the mechanism by which the rise in progesterone is caused is not yet fully understood.
Study Design, Size, Duration:
This study was a post hoc analysis of data from two multi-center, randomized, double-blind, double-dummy, active-controlled, non-inferiority trials, ENGAGE and PURSUE, conducted from June 2006 to January 2008 and from July 2010 to October 2012 respectively.
Participants/Materials, Setting, Methods:
In the ENGAGE-study, 1506 women, aged 18-36 years, were allocated to either a single injection of 150 mg CFA or daily injections of 200 IU rFSH in the first week of stimulation, using a standard GnRH antagonist protocol. In the PURSUE-study, a total of 1390 women, aged 35-42 years, were allocated to either a single injection of 150 mg of CFA or daily 300 IU of rFSH for the first week, again using a standard GnRH antagonist protocol. In both trials, daily rFSH was continued until three follicles reached >17 mm in size. All women had a body weight of between 50 and 90 kg, regular menstrual cycles and an indication for ovarian stimulation before IVF. The incidence of progesterone elevation on day of hCG-trigger in patients with CFA only or rFSH stimulation, and triggered on Day 8 of stimulation, was analyzed.
Main Results And The Role Of Chance:
Of patients with CFA only stimulation, 5.4% (13/239 patients) showed a progesterone elevation above 1.5 ng/ml on day of hCG-trigger, whereas patients with rFSH stimulation had a significant higher incidence of progesterone elevation (18.3%; 62/339 patients) (P < 0.001).
Limitations, Reasons For Caution:
Post hoc analysis of data from previously published trials could be considered as a reason for caution.
Wider Implications Of The Findings:
Future studies should evaluate whether it would be possible to prevent a premature progesterone rise in cycles stimulated with daily FSH by using a step down protocol towards the end of the follicular phase.
Study Funding/Competing Interests:
Financial/Material Support was provided by Merck & Co., Inc., Kenilworth, NJ, USA. Davis Gates is an employee of Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA and may own stock and/or hold stock options in the company. Fabiola Beligotti is an employee of MSD, Italy, a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA and may own stock and/or hold stock options in the company. Barbara Lawrenz, Nils Engelmann and Human M. Fatemi have no conflict of interest.
Trial Registration Number:
ENGAGE study: ClinicalTrials.gov identifier NTC00696800. PURSUE-study: NCT01144416.
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