Thyroid function in human pregnancy: VI. Premature deliveries and reproductive failures of pregnant women with low serum butanol-extractable iodines. Maternal serum TBG and TBPA capacities

Abstract

More numerous stillbirths, neonatal deaths, and weak infants have been reported in countries of increased thyroid underfunction and endemic goiter. At Providence Lying-In Hospital deliveries of 1,252 normothyroxinemic pregnancies were compared with deliveries of 168 registrants exhibiting hypothyroidism or low serum BEI (butanol-extractable iodine). Thirty-three uncomplicated pregnancies with low BEI values terminated without delivery of a full-term surviving infant. In 16 of these thyroxine-binding proteins were measured and were normal in 9 pregnancies. Previous reproductive histories of 97 hypothyroid or hypothyroxinemic women were matched with those of 97 control women having 2 normal BEI values before and 2 after 24 weeks before a surviving infant weighing 2,500 grams + was born. Outcome of delivery of the two groups was significantly different with p < 0.025 by the chi square test. Both in pregnancies studied and in previous reproductive histories the hypothyroxinemic women had a lesser incidence of surviving infants weighing 2,500 grams + and a higher incidence of abortions, prematurity, stillbirths, major anomalies, and progeny with subsequent retardation.