Background: Administration of antenatal magnesium sulfate (MgSO4) to pregnant women is thought to increase the synthesis of Brain-Derived Neurotrophic Factor (BDNF), which functions as a nerve-growth factor for the process of neurogenesis and also strengthen neuronal resilience in the hypoxic condition that occurs during preterm delivery. Protocols for administering antenatal MgSO4 differ between countries and institutions. One of the concerns is whether the dose is given and the time interval to delivery has a big contribution towards a better fetal outcome. These relationships have not been studied before. This study aimed to analyze the correlation of the total dose of MgSO4 and time interval to delivery with BDNF levels in cord blood.
Methods: This study enrolled 72 pregnant women who will deliver the baby prematurely, with gestational age 28-34 weeks. Subjects were divided into three protocols groups: (1) 4 g iv. only, (2) 4 g iv. initial continued with 1 g/hours until maximum 24 hours, and (3) 6 g iv. initial continued with 2 g/hours until a maximum of 24 hours. At the time of delivery, cord blood of preterm babies was collected. The antenatal MgSO4 total dose and time interval to delivery were collected, and BDNF serum levels were then measured with enzyme-linked immunosorbent assay (ELISA). The correlation between antenatal MgSO4 total dose and time interval to delivery with BDNF levels was analyzed using Spearman’s correlation test.
Result: There was a weak significant correlation of antenatal MgSO4 total dose and BDNF cord blood levels (p<0.001; r=0.381). There was no significant correlation between delivery time interval and BDNF cord blood levels (p=0.44; r=0.092).
Conclusion: Regarding the weak correlation of total dose and time interval to delivery with BDNF, we suggest that all protocols provide comparable outcomes if seen only from the BDNF increase perspective.