Progesterone rise on hCG day is negatively correlated with IVF-ET outcomes in natural cycles.

OBJECTIVE:To investigate the effect of progesterone rise on hCG day on the laboratory and clinical outcomes in natural cycles and to explore the possible factors related to the occurrence of progesterone elevation. PATIENTS AND STUDY METHODS:Retrospective analysis was performed in 1157 infertile women with decreased ovarian reserve. Eligible infertile women undergoing IVF in natural cycles were assigned to four groups according to serum progesterone levels on the day of hCG administration: group 1, P<2nmol/L; group 2, 2More