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Maternal cerebral Doppler velocimetry before, during, and after a normal pregnancy: a longitudinal study

Objective. Our purpose was to determine normative data for maternal cerebral blood flow indices. Study design. A prospective longitudinal study. Methods. The maternal middle cerebral artery was examined by transcranial Doppler ultrasound in 14 healthy women before (0–10 months prior to conception) and during pregnancy (at 8, 15, 22, 29, and 36 weeks of gestation), and twice after delivery (at 8 and 24 weeks). Middle cerebral artery blood flow velocities were recorded, and pulsatility index and cerebral perfusion pressure were calculated. Results and conclusion. Pulsatility index of middle cerebral artery peaked in mid‐pregnancy and was constantly increased between 8 and 29 weeks of gestation. The diastolic middle cerebral artery velocity remained fairly constant at about 40 cm/s during the study period, while the systolic velocity peaked at 15 weeks (mean 102 cm/s). Cerebral perfusion pressure dropped to its lowest levels in mid‐pregnancy and after delivery.