FETAL ACIDOSIS AND HYPERLACTICAEMIA DIAGNOSED BY CORDOCENTESIS IN PREGNANCIES COMPLICATED BY MATERNAL DIABETES-MELLITUS

Fetal blood samples were obtained by cordocentesis (ultrasound guided needle aspiration) from 28 pregnant Type 1 diabetic women between 20 and 40 weeks' gestation. Analysis of the deviations from normal values of blood pH and plasma lactate showed significant acidosis (p < 0.001) and hyperlacticaemia (p < 0.01) in the third trimester, but not in the second trimester. Blood P(O)2 and P(CO)2 levels did not differ significantly from normal values. The pH showed significant correlations with P(O)2 (r = 0.54; p < 0.01), P(CO)2 (r = -0.70; p < 0.001), lactate (r = -0.46; p < 0.05), fetal glycosylated haemoglobin (r = -0.53; p < 0.01), and maternal glycosylated haemoglobin (r = -0.57; p < 0.01). Plasma lactate showed significant correlations with P(O)2 (r = -0.54; p < 0.01), P(CO)2 (r = 0.50; p < 0.05), and pH (r = -0.46; p < 0.05). Neither pH nor lactate showed significant correlations with birthweight. These observations suggest that some fetuses of diabetic women are significantly acidotic and hyperlacticaemic in the third trimester. This may provide a possible explanation for the phenomenon of late intrauterine fetal death in pregnancies complicated by maternal diabetes mellitus.