1 Department of Pediatrics and Division of Biochemistry, Jewish Hospital of Brooklyn, and Department of Pediatrics, State University of New York College of Medicine at New York City
The incidence of hypocalcemia on the first day of life in mature infants born to mothers per vias naturales who had uncomplicated pregnancies and labors is 1.2%.
In our series of infants born to mothers who had complications during pregnancies and/or labors, every one had hypocalcemia on the first day of life.
Infants delivered by cesarean section because of cephalopelvic disproportion or because of "repeat" section had an incidence of hypocalcemia of 13.7% while those infants delivered by section because their mothers had pathologic states during pregnancy had an incidence of 36.8%.
The effect of complications during pregnancy and/or labor was not apparent when we studied the incidence of hypocalcemia in premature infants on the first day of life. We noted that the avenue of birth or the presence or absence of complications during pregnancy and/or labor did not affect significantly the incidence of hypocalcemia on the first day of life.
There is a significant positive correlation between weight of the premature infant and the total concentration of calcium in the plasma.
There was no significant statistical correlation between the mean concentrations of protein and of calcium in the serums of the premature infants studied.
We have speculated that, because premature births occur during the third trimester of pregnancy, the adrenocorticosteroids, which attain their highest concentration in the maternal serum during this period, may exercise a depressing effect on the concentrations of calcium in plasma of infants.
Submitted on October 31, 1955