PLACENTAL IMPLICATIONS FOR PREGNANCY COMPLICATIONS IN THE CHIMPANZEE (PAN-TROGLODYTES)

Placentas from 28 term chimpanzee pregnancies, including two sets of dichorionic‐diamniotic twin‐pregnancies, were examined and compared histopathologically with those obtained from 171 small‐for‐dates (SFD), 306 premature, and 77 pregnancy toxemic human infants. Term infant and placental weights for the chimpanzee were generally smaller than for any of the human categories studied. Macroscopically, the chimpanzee placentas showed a high frequency of extrachorialis, infarctions, intervillous thrombi, and marginal hemorrhages, pathologies frequently associated with pregnancy toxemia and abruptio placenta in the human being. Yet, ultrastructurally, the chimpanzee chorionic villi evidenced well‐developed organella, syncytial microvilli, and chorionic capillaries, although villitis and inflammation of the membranes and cord were not infrequently seen. These findings suggest that chimpanzees may suffer the same obstetric complications seen in human pregnancies. Copyright © 1990 Wiley‐Liss, Inc., A Wiley Company