Obstetric problems in diabetic pregnancy – The role of fetal hypoxia

Perinatal mortality has not decreased over the last two decades in pregestational diabetic pregnancies. Stillbirth rate is 4–6 times and neonatal mortality 2–4 times higher in diabetic than in non-diabetic pregnancies despite modern electronic fetal surveillance methods. Majority of late stillbirths are “unexplained”, many of which are presumably caused by fetal hypoxia. Both experimental and clinical studies have shown that fetal hyperglycaemia and hyperinsulinaemia can independently cause fetal hypoxia, which ultimately can lead to fetal death. Poor glycaemic control is associated with perinatal complications. Sharp increases in amniotic fluid erythropoietin levels indicate fetal hypoxia in diabetic pregnancy. Fetal erythropoietin concentrations correlate directly with maternal HbA1c levels. It is therefore important to maintain near-normal glycaemic level throughout pregnancy. Measurement of amniotic fluid erythropoietin level is a new way to detect fetal hypoxia antenatally. Sufficiently large controlled studies are needed before definitive answer of the clinical utility of amniotic fluid erythropoietin measurements in diabetic pregnancies can be determined.