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[Spontaneous ovulation in in vitro fertilization-embryo transfer cycles using gonadotropin-releasing hormone
1Center of Reproductive Medicine, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
Objective:
To investigate the premature spontaneous ovulation rates in in vitro fertilization-embryo transfer (IVF-ET) cycles using gonadotropin-releasing hormone antagonist (GnRH-ant) and gonadotropin-releasing hormone agonist (GnRH-a), as well as the risk factors for premature spontaneous ovulation.
Methods:
The rates of premature spontaneous ovulation in a total of 10 612 cycles using GnRH-ant or GnRH-a were compared. Matched case-controlled study and binary logistic regression model were conducted to analyze the risk factors for premature spontaneous ovulation.
Results:
The spontaneous ovulation rate in the whole for GnRH-a cycles was 0.15% (13/8 514), compared with a 1.62% (34/2 098) in GnRH-ant cycles (P<0.01). Further matched controlled study and regression analyze found out that higher basal FSH level was a predominant risk and prediction factor for spontaneous ovulation (OR=1.20, P=0.009).
Conclusions:
In GnRH-ant cycles, spontaneous ovulation rate is about 10 times than which in GnRH-a cycles. Diminished ovarian function is a predominate risk factor for premature spontaneous ovulation.
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