[Sodium and potassium concentrations in whole blood and the serum of pregnant females and newborn infants].

The behaviour of sodium-potassium level in whole blood and serum of 464 mothers and their newborns was studied intra partum and immediately after delivery. There is a control group of 100 non pregnant women without hormonal contraception. During pregnancy there is a marked decrease of serum sodium concentration levels. In pathological pregnancies a small increase of serum-sodium-levels is observed in comparison to normal pregnancy. Multiparas and female neonates show increased concentrations of sodium in comparison with the control group. The serum-potassium levels of pregnant women are significantly increased compared with non pregnant women. The sodium-potassium concentration of newborns with Apgar 5-7 is significantly higher than that of children with an Apgar 8-10. The potassium level of all the newborns is increased compared with the potassium concentrations of their mothers. The sodium-level in whole blood of pregnant and non pregnant women is increased, whereas the potassium level is reduced in contrast to a low serum-sodium level and a high serum-potassium level.