Objective  To investigate the predictive value of umbilical vein blood brain-derived neurotrophic factor(BDNF) level for brain injury of neonates delivered by the pregnant with gestational diabetes mellitus(GDM).

  Methods  A total of 92 full-term birth pregnant women with GDM were selected as observation group, while 80 healthy pregnant women were selected as control group. Based on the result of brain ultrasound, magnetic resonance imaging (MRI) and neonatal behavioral neuroassay (NBNA) score at 3 days postpartum, the neonatal brain injury conditions were determined. The umbilical vein blood BDNF levels were measured by enzyme-linked immunoassay (ELISA). The incidence of brain injury was compared between the observation group and the control group. The predictive value of cord blood BDNF for brain injury in full-term newborns was evaluated by Receiver Operating Characteristics (ROC) curve.

  Results  The incidence of neonatal brain injury, and BDNF level in neonatal cord blood in the observation group were significantly higher than those in the control group (P < 0.05). The neonatal NBNA score in the observation group was significantly lower than that in the control group (P < 0.05). In observation group, the level of BDNF in neonatal cord blood of the brain injury neonates was higher, and the neonatal NBNA score in the brain injury group was lower than that in the non-brain injury ones (P < 0.05). There were no differences in BDNF level and NBNA score of brain injury between brain injury neonates and non-brain injury newborns in the control group (P>0.05). When the BDNF level was 13.8 μg/L, the Yodeng index was the highest, with its value of 0.346 and the area under the curve was 0.732, with sensitivity and specificity of 79.71% and 55.86%, respectively.

  Conclusion  The risk of brain injury in the full-term newborns delivered by GDM mothers is higher, early detection of BDNF in umbilical vein blood has a good accuracy in predicting the occurrence of brain injury.