Table 1. Etr Values in Cord Blood and in Infants and Children

to 2 days were all elevated (1.17—1.37) and within the hyperthyroid range for adults. Values in infants age 2 weeks and older and in children age 1—15years all fell within the normal adult range. These findings suggest that the ETR can be used as an ancillary measure of thyroid func. tion in infants and children. In the immediate postpartum period, however, ETR values may be normally in the adult hyperthyroid range.