[Measuring the turbidity of amniotic fluid, a possibility to assess fetal maturity before birth (author's transl)].

At the end of gestation, depending on maturation of the fetus and especially of its skin, vernix caseosa is detached into amniotic fluid. The changes of amniotic fluid turbidity can be quantitatively verified with a fotometer (filter for 578 nm, 10 mm disposable cuvettes). The turbidity of amniotic fluid was measured in 125 cases. No correlation was found between turbidity and length of gestation from day 261 to day 287 after last menstruation. In contrast, there is strong and significant contingency between turbidity of amniotic fluid and maturity of fetal skin (quantity of vernix caseosa) or clinical maturity assessed according to Farr et al. Finding a turbidity below 0.5 U on extinction scale of the fotometer, the fetus is not fully mature in 50% of these cases; placental dysfunction can be excluded with high probability. In contrast, two thirds of the children with high turbidity of amniotic fluid (more than 1.0 U on extinction scale) had clinical signs of placental dysfunction.