Endocrinology of pregnancy. I. Denominations of concentrations of triiodothyronine, thyroxine, effective thyroxine, thyreotrophin and growth hormone in normal pregnancy, labour and in cord blood.

Concentrations and activities of the following agents were estimated: triiodothyronine (T3), thyroxine (T4), effective thyroxine (ETR), thyreotrophin (TSH), and growth hormone (HGH). Blood samples were collected in pregnancy, labour and from the umbilical cord of the newborns. It was demonstrated that in normal pregnancy the concentrations of T3, ETR, and TSH did not differ significantly from the values considered as normal in non-pregnant women. The concentration of T4 was distinctly higher in the course of pregnancy (139 to 157 nmol/l versus 110 nmol/l in non-pregnant subjects). The HGH concentration increased during pregnancy from 5.6 to 14.3 micrograms/l. The cord blood demonstrated comparable values of ETR and HGH and in half of the cases of TSH also with those observed in the mothers. In the other one half of the cases, TSH activity was fourtimes higher than the material value. The T3 and T4 were lower than values in the mothers. The results presented are the normal values for further planned investigations of endocrinology of pregnancy, especially for studies into course of pregnancy in women who work in noxious conditions.