OBJECTIVE: To determine normal ranges for various Doppler flow velocity indices of the fetal middle cerebral artery (MCA) and their trends in normal pregnancies at Korle Bu Teaching Hospital, Accra, Ghana.METHODS: A prospective cross-sectional study was conducted at Korle Bu Teaching Hospital in 2015. Included women had a singleton pregnancy of 20-40weeks' duration, dated using an early ultrasonography scan, and normal fetal growth. Interviews were conducted to collect data on sociodemographic characteristics, followed by Doppler ultrasonography of the MCA. The resistive index, pulsatility index, systolic-to-diastolic ratio, and peak systolic velocity of the MCA were determined for all participants.RESULTS: Overall, 458 pregnant women were recruited. The peak systolic velocity increased with advancing gestational age and a positive correlation of r=0.725 (P<0.001) was demonstrated between the peak systolic velocity and the gestational age. The resistive index, pulsatility index, and systolic-to-diastolic ratio of the MCA decreased with advancing gestational age in a parabolic pattern.CONCLUSION: The reference curve for the peak systolic velocity increases with gestational age, whereas the other indices decrease in a parabolic pattern.
Adult Blood Flow Velocity