Do early luteal serum progesterone levels predict the reproductive outcomes in IVF with oral dydrogesterone for luteal phase support?

Our study suggests a positive association between early P4 levels and reproductive outcomes in IVF using oral dydrogesterone for luteal support. The inconsistencies between our results and those of other studies suggest that extrapolation is impractical. Further larger prospective cohort studies should be conducted to determine reliable thresholds that could be used to personalize luteal phase support.