[Stereoptical study of the microvilli in intrauterine growth retardation placenta with different ponderal indexes].

Two groups of 6 intrauterine growth retardation (IUGR) placentae each from normal ponderal index (NPI) or low ponderal index (LPI) and 10 placentae from normal pregnancy as control were quantitatively analyzed with light and electron microscopic morphometry. The results showed that the placental weight, volume, surface area of the villi and villous fetal capillary in IUGR were significantly reduced compared with those in the control group. Not only were the placental weight, volume, surface area of villi, villous capillary, intermicrovillous surface density and absolute values surface area of the microvilli in NPI group significantly lower than that in the control group, but also lower than in LPI group. This suggests that there was a functional deficiency of placenta in IUGR placentae, nonetheless, the changes of functional structures in IUGR placentae with different ponderal indexes were not the same. The stereoptical study with light microscopy and with the electron microscopic level in confirming that NPI group has a more severe deficiency in placental function than in the LPI.