[Studies on meconium-like substances in the urine of mother and neonate during perinatal period].

: It is well known that the entry of amniotic fluid into the mother's circulation may result in the occurrence of amniotic embolism, and aspiration of meconium by the neonate may cause meconium aspiration syndrome. To study meconium-like substances detected in the urine of mother and neonate during the perinatal period, the authors carefully assayed the Urinary Meconial Index (UMI) in subjects including 100 pregnant women, 171 parturient women, 171 neonates and 68 samples of amniotic fluid. Through the UMI assay, the frequency of the appearance of high UMI, the mode of delivery at high UMI and its effect upon both mother and neonate were studied and the following findings obtained. The entry of meconium into the mother's circulation occurs during labor pains and may be excreted into the mother's urine (6.4%). Labor pains enhance the entry of meconium into the mother's circulation and the entry takes place even in the absence of any clinical signs of rupture of the membranes (p less than 0.01). The entry of meconium into both mother and neonate occurs at a higher rate in dystocia and in cases with meconium-stained amniotic fluid (p less than 0.05). Even in the absence of marked symptoms such as those in meconium aspiration syndrome, the aspiration of meconium affects postnatal course of the newborn (positive CRP, early appearance of bilirubinemia: p less than 0.05).