Relationship of progesterone/estradiol ratio on day of hCG administration and pregnancy outcomes in high responders undergoing in vitro fertilization

ObjectiveTo evaluate the predictive value of a serum P/E2 ratio measured on the day of hCG administration regarding pregnancy outcomes in high responders undergoing IVF.DesignRetrospective study.SettingTeaching hospital.Patient(s)Two hundred twenty-three infertile women classified as high responders in IVF-ET cycles.Intervention(s)Eligible infertile women undergoing IVF were assigned to four groups according to serum P levels on the day of hCG administration: group 1, P≤0.9 ng/mL; group 2, 0.9 < P≤1.4 ng/mL; group 3, 1.4 < P≤2.0 ng/mL; group 4, P>2.0 ng/mL. The relationship of E2 level and P/E2 ratio on the day of hCG administration and pregnancy outcomes was analyzed.Main Outcome Measure(s)Implantation and pregnancy rate.Result(s)Patients in group 4 had highest E2 level and P/E2 ratio, as well as lowest implantation and pregnancy rates. Using P for grouping, the sensitivity/positive predictive values (%/%) of P/E2 ratio in the four groups were 15/66, 30/65, 30/60, and 25/41, respectively.Conclusion(s)Using the level of a single sex hormone on hCG day to predict pregnancy outcome in high responders undergoing IVF is confounding, whereas using a P/E2 ratio on hCG day is theoretically reasonable. However, the low sensitivity and positive predictive value make the use of P/E2 clinically unfeasible.