Significance of premature progesterone rise in IVF

PURPOSE OF REVIEW: The current review will focus on the cause of premature progesterone and its impact on endometrial receptivity and endometrial gene expression. RECENT FINDINGS: Premature progesterone rise in stimulated IVF cycles seems to have a negative impact on the pregnancy rate. The current knowledge on the cause of a premature progesterone rise is still limited; however, it seems that overstimulating the ovaries during the end of the follicular phase will lead to a premature progesterone rise. The negative impact on the outcome is mainly due to reduced endometrial receptivity as can be seen in the altered endometrial gene expression. SUMMARY: Future studies should focus on how ovarian stimulation can be tailored according to individual requirements of the patients, aiming on preventing a possible progesterone rise during follicular phase of stimulated IVF cycles.