To describe changes in brain velocities in fetuses with intrauterine open spina bifida repair. A cohort of fetuses with open spina bifida selected for open fetal microneurosurgery for intrauterine spina bifida repair were recruited. Middle cerebral artery peak systolic velocity (MCA-PSV) was evaluated by Doppler ultrasound. The MCA- PSV Doppler values were converted to multiples of median (MoM) according to gestational age. MCA-PSV Doppler values before and after open fetal surgery were compared. During the study period, 64 fetuses were recruited. Doppler recordings were successfully obtained in all fetuses at a median gestational age of 24.85 weeks. All cases showed normal values of MCA-PSV before open fetal surgery. MCA-PSV values after fetal surgery were significantly increased in comparison to those observed before fetal intervention (0.88 vs. 0.97, p = 0.007). Open fetal microneurosurgery was associated with increased brain systolic velocities.