Gonadotropins, including human chorionic gonadotropin (hCG), have been used since and for several decades to treat infertility by ovarian stimulation. hCG is the most important protein for embryogenesis and embryo development and implantation in uterus upon fertilization of oocytes. The hCG used for in-vitro fertilization (IVF) is being extracted from urine of pregnant women, and it does inevitably contains other proteins secreted into urine. The presence of other proteins varies from batch to batch, and it can be significantly high. Due to the fact that many of the proteins identified in these formulations can trigger an allergic reaction, which, in turn, can affect the embryogenesis and prevent embryo implantation, it is very important to check the amount and type of contaminant proteins in pharmaceutical formulations. It was found that the total protein content varied from batch to batch, and a large number of contaminant urinary proteins were identified in all analyzed samples except for the recombinant product.
Part of the book: Embryology