Lee B, et al. - This study is performed to scrutinize the levels of estrogen and progesterone in the maternal plasma of IVF, non-IVF fertility treatment (NIFT), and spontaneous pregnancies at the time of chorionic villus sampling (CVS). Circulating 17-β-estradiol and progesterone remain persistently raised in the late first trimester in mothers of pregnancies conceived with IVF compared to those who conceived spontaneously even after discontinuation of hormone supplementation, possibly because of placental reprogramming leading to elevated hormone production.