Post trigger progesterone levels as a predictor of oocyte recovery rate

Abstract Study question Do progesterone (P) levels the day after trigger for oocyte maturation impact the oocyte recovery rate? Summary answer A progesterone cutoff value of ≤ 5.0 ng/ml the day after trigger for oocyte maturation is associated with a lower oocyte recovery rate. What is known already Oocyte maturation and embryo development are controlled by intra-ovarian factors such as steroid hormones. P exists in the follicular fluid, and it is known to mediate some luteinizing hormone (LH)- initiated periovulatory events through autocrine/paracrine mechanisms that help mediate granulasa cell luteinization and oocyte maturation. More importantly, a rise in P levels is associated with an adequate follicular rupture. To date, no study has evaluated if lower P levels after oocyte maturation induction are a reflection of impaired physiological periovulatory mechanisms required for the oocyte release from the follicular wall. Study design, size, duration This monocentric retrospective analysis from January 2017 to December 2021 included 435 controlled ovarian hyperstimulation cycles for in vitro fertilization (IVF)/ egg freezing. Serum P, estradiol (E2), bHCG, and LH levels were measured the day after trigger for oocyte maturation to assure adequate luteinization. Participants/materials, setting, methods Women <4O years, that underwent controlled ovarian hyperstimulation with a GnRH antagonist protocol and final oocyte maturation (when ≥2 follicles reached ≥18 mm in diameter) induction with dual trigger (Leuprolide acetate and hCG) were segregated into two groups: Group 1: progesterone cutoff value of ≤ 5.0 ng/ml the day after trigger; Group 2: progesterone cutoff value of ≥ 5.1 ng/ml the day after trigger. Main results and the role of chance 147 cycles in Group 1 were compared with 288 cycles on Group 2. No significant differences were noted in mean patient’s age, BMI, baseline FSH, AMH, baseline antral follicle count, serum P and E2 levels the day of trigger, total dose of gonadotropins, day of trigger as well as serum E2, LH, and bHCG levels the day after trigger among cohorts. A total of 5765 oocytes were retrieved: 1703 corresponding to group 1 and 4692 to group B. Women with progesterone levels higher than ≥5.1 ng/ml the day after trigger had a greater number of oocytes retrieved compared to women with a progesterone cutoff value of ≤ 5.0 ng/ml (16.3 ± 9.1 versus 11.5 ± 7.4, p = < 0.0001). The oocyte/follicle rate was also significantly higher in women in Group 2 vs Group 1 (80.3% vs 63.7%, p = 0.003) However, the mature oocyte (MII) rate was comparable among cohorts (Group 1: 78.0 ± 20.2% vs Group 2: 78.8 ± 17.7%, p = 0.38). Limitations, reasons for caution The retrospective nature of the study, small sample size, selected progesterone cutoff value, and progesterone assay techniques compared to other ART centers may limit the external validity of our findings. Wider implications of the findings Our findings suggest for the first time that lower progesterone levels after final oocyte maturation induction may be a result of compromised mechanisms associated with the release of the oocyte from the follicular wall as demonstrated by a lower oocyte recovery rate. Trial registration number NA