How to Determine the Ideal Increased Progesterone Levels Cutoff During Fresh In Vitro Fertilization Cycles: Is it Time to Move Forward-A Short Commentary

That increased progesterone(P) that is present on the day of human chorionic gonadotropin (HCG)trigger has an effect on the probable chances of a pregnancy resulting following a fresh embryo transfer has been a point that can be debated over the last 25 years [1-3]. A meta-analysis conducted by Venetis et al in 2013, confirmed the negative effect of progesterone on pregnancy following an ET [3]. They Further confirmed that by using proper analytical approaches one can find this correlation [4]. How this effect is brought about is by changing endometrial receptivity, an approach tested both by basic along with clinical research. Most importantly this support comes from cycles in which increased P do not affect if the embryos are frozen and transferred in subsequent cycle of frozen-thawed embryos [3]. Hence a proposal of freeze all/ freeze only policy was suggested as an answer to manage increased P found by the end of follicular phase.