IGFBP1 and Infertility: Addition of 0.5 μg/ml prednisolone to the decidualization treatment showed no significant effect on PRL or IGFBP1 secretion in hESF cultured fresh (Figure 2A; 3/4 primary infertile, 1/4 unknown fertility) or frozen down before seeding for decidualization treatments (Figure 2B; 3/4 secondary infertile, 1/4 fertile).