215 women with full-term monocyesis, including 25 apparently healthy individuals, 190 being at high infection risk (34 with oligohydramnios, 44 with hydramnios, and 112 with normal amniotic fluid volume), their neonates, and placentas were examined. In women with infectious diseases, hydramnios and oligohydramnios were shown to be always accompanied by a complicated pregnancy; every three women had a complicated labor; 72% of babies had complicated early neonatality. At the same time, a morphological study revealed pronounced histological changes in all placentas: with oligohydramnios, there were prevalent circulatory and dystrophic disorders that were characterized by poorer placental blood supply and that led to impaired fluid transport through the placenta and fetal membranes to the amniotic cavity; with hydramnios, there were inflammatory and dystrophic changes that prevented fluid from being absorbed in the opposite direction.