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

OBJECTIVE: To evaluate the predictive value of a serum P/E(2) ratio measured on the day of hCG administration regarding pregnancy outcomes in high responders undergoing IVF.
DESIGN: Retrospective study.
SETTING: Teaching 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<or=1.4 ng/mL; group 3, 1.4 < P<or=2.0 ng/mL; group 4, P>2.0 ng/mL. The relationship of E(2) level and P/E(2) 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 E(2) level and P/E(2) ratio, as well as lowest implantation and pregnancy rates. Using P for grouping, the sensitivity/positive predictive values (%/%) of P/E(2) 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/E(2) ratio on hCG day is theoretically reasonable. However, the low sensitivity and positive predictive value make the use of P/E(2) clinically unfeasible.