Calcium Studies in the Newborn

The purpose of this investigation was to study the relationship between the calcium of the cord blood and that of the peripheral blood during the first 10 days of life. If a low cord blood calcium regularly were associated with a low calcium during the first 10 days of life, then hypocalcemic tetany of the newborn could be predicted and prevented. In the 47 cases thus far examined there is a rather constant relationship between the cord and the postnatal blood though not of the nature mentioned above. There is a tendency for the serum calcium to assume values lower than the cord blood during the first 4 days of life and then to rise toward the prenatal level during the next 5 days.

The average calcium of the serum of cord blood was 11.60.

The average deviation of peripheral blood from cord blood of the same individual was

—1.04 for the 1st to 2nd days (11 cases)

—1.21 for the 3rd to 4th days (16 cases)

—0.36 for the 5th to 6th days (8 cases)

+0.55 for the 7th to 9th days (12 cases)

While this work was in progress Bakwin 1 reported similar findings, based on data obtained from different sources. Our figures were obtained from the cord and postnatal blood of the same babies, whereas Bakwin compared the results of 67 examinations made during the first 10 days of life with calcium determinations on 300 cord bloods performed some years previously.

Serum inorganic phosphorus tests were done on a few cases but are not sufficiently numerous to warrant reporting.

Studies of other factors, inorganic phosphorus, total protein, blood cell concentration, feeding, etc., are being continued to determine what circumstances may influence the calcium level variations.