Delayed luteo-placental shift of progesterone production in IVF pregnancy

Abstract

The luteal contribution to maternal serum levels of progesterone is much higher in IVF pregnancies compared with normal pregnancies. This is sustained throughout the first trimester without the need for luteal support and obscures the placental contribution of progesterone for much longer than in normal pregnancies. Progesterone or hCG supplements may therefore be unnecessary in IVF pregnancy.