Randomized controlled study comparing effect of magnesium sulfate with placebo on fetal umbilical artery and middle cerebral artery blood flow in mild preeclampsia at ≥34 weeks gestational age

Aims: The aim of this study was to evaluate whether prophylactic magnesium sulfate given in women with mild preeclampsia or gestational hypertension brings any significant change in umbilical artery and fetal middle cerebral artery pulsatility index. Material and Methods: Forty-eight women with gestational age greater than 34 weeks with mild preeclampsia or gestational hypertension were randomly assigned to receive either magnesium sulfate or placebo. Pre- and post-magnesium sulfate pulsatility index of umbilical and fetal middle cerebral artery were compared by Mann-Whitney U-test between the groups. Within-group comparison was conducted using Wilcoxon's signed rank test. Results: There was a significant reduction in the post-magnesium sulfate umbilical artery pulsatility index in the intervention group (median 0.88 [0.82-1.03]) when compared to the placebo group (median 1.00 [0.89-1.10]). Post-magnesium sulfate fetal middle cerebral artery pulsatility index in the intervention group (median 1.78 [1.63-1.98]) did not show a significant change compared to the placebo group (median 1.65 [1.42-1.91]). Within-group comparison showed change in both variables after treatment in the intervention group. Conclusion: Magnesium sulfate produces a significant decrease in fetal umbilical artery and middle cerebral artery pulsatility index.