THE RELATIONSHIP OF THE POSTPARTUM RISE IN SEROMUCOID TO PRIMIGRAVID PLACENTAL WEIGHT

The postpartum rise in seromucoid, which is an heterogenous acid‐soluble glycoprotein sub‐fraction, is related to placentalweight in primigravidae but not in multigravidae. This observation supports the view that primigravidae, who have had no previous exposure to paternal histocompatibility antigens, depend on glycoprotein to mask the trophoblast from the cellular immune response. With previous exposure to paternal histocompatibility antigens, as in multigravidae, the maternal antibodies so formed may coat the trophoblast and thus reduce the need for a covering of nonspecific glycoprotein.