Diabetic Pregnancy and Fetal Consequences

Abstract

Perinatal morbidity and mortality, congenital malformations, abnormal fetal growth, both spontaneous and iatrogenic preterm birth, hypoxic complications, and trauma during delivery are increased in diabetic pregnancies. Perinatal mortality in diabetic pregnancies is still three to five times higher than the perinatal mortality in the general population. Stillbirths during the last weeks of pregnancy are often considered unexplained, although recent studies indicate that most of these stillbirths are caused by fetal chronic hypoxia. Importantly, perinatal mortality has not changed during the past 3 decades in diabetic pregnancies, which emphasizes the need to find new methods and strategies to improve perinatal outcome. Congenital malformations have decreased in pregestational diabetic pregnancies because of general improvement of glycemic control among diabetic women. However, the rate of fetal malformations is still two to four times higher in type 1 and type 2 diabetic pregnancies than in the general population. Prepregnancy counseling decreases the risk of fetal malformations. Efforts should be made to improve the attendance of diabetic women in prepregnancy clinics. Fetal overgrowth during the last trimester of pregnancy is the most common fetal complication in diabetic pregnancies. Accurate estimation of fetal weight by ultrasound is especially difficult in macrosomic fetuses. Magnetic resonance imaging can be used to assess fetal total volume, shoulder width, and fat amount in addition to obtaining accurate pelvic measurements. More studies on the clinical use of magnetic resonance imaging in obstetrics are urgently needed. Increased fetal erythropoietin (EPO) level is an indicator of fetal chronic hypoxia, which can be detected antenatally by measuring amniotic fluid EPO concentration. Sufficiently large controlled studies are needed before amniotic fluid EPO measurement can be recommended for clinical use.