Urinary Human Chorionic Gonadotropin (hCG), Intramuscular or Subcutaneously Administered, Yields higher hCG Serum and Follicular Levels Than Recombinant hCG in Egg Donors. - Vidal, C.; Zuzuaregui, J.; Epifanio, R.; Simon, C.; Remohi, J.; Pellicer, A. (Fertility & Sterility, 2005)