Gonadotropin Salgılatıcı Hormon (GnRH) Agonist Tetiklemesi Uygulanan In-Vitro Fertilizasyon (IVF) Sikluslarında Oosit Verimi ve Oosit Matürasyonunu Belirleyen Faktörler

Abstract

Özgen, B.Ö., Factors Affecting Oocyte Yield and Oocyte Maturation in In Vitro Fertilization (IVF) Cycles Triggered with a Gonadotropin-Releasing Hormone (GnRH) Agonist, Hacettepe University Faculty of Medicine, Department of Obstetrics and Gynecology, Residency Thesis, Ankara, 2026. The aim of this study was to evaluate the clinical, hormonal, and stimulation-related factors affecting the oocyte retrieval rate (ORR), oocyte maturation rate (OMR), and mature oocyte-to-aspirated follicle ratio (MPA) in ovarian stimulation cycles triggered with GnRH agonist for final oocyte maturation. This retrospective study was conducted at the Reproductive Medicine and Infertility Unit of Hacettepe University Faculty of Medicine, Department of Obstetrics and Gynecology, and included the first IVF/ICSI cycle of 282 patients who underwent GnRH agonist triggering. Factors associated with ORR, OMR, and MPA were analyzed using beta-binomial regression models. In addition, potential differences in these associations according to the pituitary suppression protocol, namely GnRH antagonist and progestin-primed ovarian stimulation (PPOS), were evaluated. In multivariable analysis, increasing female age was associated with lower ORR (aOR=0.97; 95% CI: 0.94–0.99; p=0.013). Higher total gonadotropin dose was also associated with decreased ORR (aOR=0.74 per 1000 IU increase; 95% CI: 0.60–0.92; p=0.006). Low trigger-day progesterone levels (≤1.01 ng/mL) were associated with lower ORR compared with the middle progesterone tertile (1.01–1.58 ng/mL) (aOR=0.74; 95% CI: 0.55–1.00; p=0.052). No significant differences were observed between PPOS and antagonist protocols with respect to ORR, OMR, or MPA. In addition, basal LH level, BMI, basal estradiol, trigger-day estradiol, AMH, presence of PCOS, stimulation duration, and suppression protocol were not identified as independent predictors of ORR. No independent significant predictor of OMR was identified, whereas low trigger-day progesterone level was the only significant predictor of MPA. Interaction analyses demonstrated that the effect of total gonadotropin dose on ORR varied according to the suppression protocol (p=0.0092). In antagonist cycles, both low basal LH levels (OR=0.57; 95% CI: 0.38–0.88; p=0.0428) and high basal LH levels (OR=0.55; 95% CI: 0.32–0.92; p=0.0351) were associated with lower MPA. In conclusion, advanced female age and higher total gonadotropin dose were associated with lower ORR in IVF/ICSI cycles triggered with GnRH agonist. Although basal LH level was not identified as an independent predictor in the overall study population, it was associated with MPA in antagonist cycles. Furthermore, the negative effect of increasing gonadotropin dose on ORR was more pronounced in PPOS cycles. These findings suggest that oocyte yield may be influenced by patient characteristics, stimulation-related parameters, and the suppression protocol used.