The prevalence and factors associated with umbilical arterial doppler abnormalities in women with pre-eclampsia at Mulago hospital

Abstract

Introduction: Umbilical artery Doppler velocimetry detects fetuses at risk of asphyxia from IUGR before changes in the CTG and biophysical score are evident. This has made it a primary fetal surveillance tool in pre-eclampsia in developed countries with resultant reduction in perinatal mortality by 29%. However, its routine use in high risk pregnancies is currently not feasible in resource limited settings. The objective was to determine the prevalence and factors associated with UA Doppler abnormalities in women with preeclampsia from 28 weeks of pregnancy so as to identify a subpopulation of these women who would require routine UA Doppler velocimetry to improve perinatal outcomes in a resource limited context. Methods: This was a cross-sectional analytical study at Mulago NRH conducted between June and September 2014. A total of 155 women with pre-eclampsia between 28 and 42 weeks of pregnancy with live singleton fetuses underwent UA Doppler sonography to determine the RI, S/D ratio, AEDV and RF patterns. The data were entered into EPIDATA 3.1 and exported to STATA version 12 for analysis. Results: The overall prevalence of UA Doppler abnormalities was 31.6%. High RI, high S/D ratio, AEDV and RF were found in 25.8%, 31.6%, 7.7% and 4.5% of the population respectively. The main factors associated with UA Doppler abnormalities were gestational age below 35 weeks (AOR=8.1, 95% CI: 2.91-22.76, P<0.001), severe pre-eclampsia with heavy proteinuria (AOR=7.3, 95% CI: 2.82-18.87, P<0.001), and multiparity (AOR=5.3, 95% CI: 1.52-18.53, P<0.001). Severe pre-eclampsia comprised 61% (n=95) of the study population. Maternal age and pre-eclampsia with light proteinuria had no association with UA Doppler abnormalities. Conclusion: UA Doppler abnormalities are very common in pre-eclampsia. Gestational age below 35 weeks and heavy proteinuria were the main associated factors of these abnormalities