Abstract:

Background: Doppler velocimetry of the fetal umbilical, middle cerebral artery and its cerebroplacental ratio (CPR is a non-invasive evaluation tool of fetal wellbeing. Variation of Doppler indices above or below normal limit with certain changes of the normal Doppler waveform pattern can be used as a marker in the diagnosis of placenta insufficiency and possible prediction of perinatal outcomes.

Objective: To determine the prevalence of abnormal placenta Doppler, associated risk factors (obstetrics risk), and its association to perinatal outcome.

Methods: A longitudinal study was conducted at Bugando Medical Centre in Tanzania over a period of six months. A 393 gravid patients from 28 weeks of gestation age were recruited. Doppler ultrasound evaluation of umbilical and Middle cerebral arteries was performed and CPR was calculated. Newborn assessment was done 24 hours after delivery to determine perinatal outcomes. Collected data was analysed using STATA software version 13.

Results: Among 393 recruited participants, prevalence of abnormal placental Doppler was 17.05%. In clinical categorization; the prevalence was higher 61.7% in high-risk pregnancy compared to 1.4% in low-risk group. Hypertensive disorder of pregnancy (OR 32.4; 95% CI [12.2-86.4]; p-value<0.001), PROM (OR 22; 95% CI [5.9-80.0]; p-value < 0.001), diagnosis of unspecified insufficient (OR 18.3; 95% CI [3.8-87.2]; p-value <0.001) and APH (OR 9.9; 95% CI [1.9-50]; p-value 0.006)), were significantly associated with abnormal placenta Doppler study, Abnormal CPR was significant associated with adverse perinatal outcomes.

Conclusion: Prevalence of abnormal placenta Doppler (CPR) was high in our setup, based on clinical categorization it become a potentially screening tool to be done in detection of abnormal placental blood flow, in high risk pregnancies. It association with poor peri-natal outcomes as seen in this study, makes it among investigation of choice in identifying fetus with intrauterine complication.