Levels of steroid binding proteins and steroids in human preovulatory follicle fluid and serum as predictors of success in in vitro fertilization embryo transfer treatment

In an attempt to identify the embryos and cycles that have the best chances of resulting in establishment of pregnancies, after in vitro fertilization-embryo transfer (IVF-ET) treatment, the concentrations of sex hormone-binding globulin (SHBG) and cortisol-binding protein (CBP) were measured, using two new enzyme-linked immunosorbent assays in serum and follicle fluid (FF) from 30 women (125 FF) undergoing IVF-ET. The concentrations were compared to those of total estradiol and total progesterone, and correlated to oocyte cleavage and the establishment of pregnancies. Serum concentrations of CBP were significantly higher in women who became pregnant (1469 ± 108) nm (±sem)) than in those who did not (CBP, 1200 ± 58 nm; P ≤ 0.05). The concentrations of SHBG were not significant different in these two groups of women (72.4 ± 9.3 and 60.8 ± 4.2 nm, respectively; P ≥ 0.10). By contrast, in FF significantly higher concentrations of both SHBG and CBP were found in women achieving pregnancy (SHBG, 56.1 ± 2.8 nm;...