Combined Maternal Serum C3 Activation and Uterine Artery Doppler at 14-20 Weeks as Predictors for Pre-Eclampsia in Primigravida

Background: Preeclampsia is a multisystem disorder of pregnancy, which complicates 3%-5% of pregnancies in the western world. It is a major cause of maternal morbidity and mortality worldwide. The cardinal clinical features of the condition are hypertension and proteinuria occurring after 20 weeks gestation in women who were not previously known to be hypertensive. Objective: This study was aimed to assess the efficacy of C3 estimation and measurement of bilateral uterine artery Doppler before 20 weeks of pregnancy for prediction of preeclampsia in primigravida. Methods: The study was performed at the Antenatal Care Unit, Obstetrics and Gynecology Department, Sayed Galal Hospital, Al Azhar University on 131 pregnant women at 14-20 gestational weeks during period from July 2017 to December 2017 gestation attending. Results: On follow up the population of the study 131 pregnant women had completed the study that were classified to 119 (90.8%) with no pre-eclampsia and 12 (9.2%) developed preeclampsia, As regards the Patients characteristics there was no statistical significant difference between the two groups as regard age, height, weight, gestational age, SBP and DPB at enrollment (p-value>0.05). There was a significant difference regarding BMI as (p value < 0.05), with more increasing BMI and decreasing gestational age at delivery in preeclampsia group in comparison with the no preeclampsia group. As regards the C3, there was statistically highly significant difference between the two groups regarding serum C3 level as p value <0.05, with lower levels of C3 serum levels in preeclampsia group. Receiver operator characteristics (ROC) curves were constructed for estimating the association between pre-eclampsia and serum C3 level. A significant association was found with serum C3 level being a significant predictor with lower values in cases with pre-eclampsia than in normal cases [area under the curve (AUC) = 0.935, 95% CI (0.878 to 0.9711.35), best cut off (≤53.1), sensitivity of 83.3%, specificity of 100% positive predictive value (PPV) of 100% and negative predictive value (NPV) of 98.3%. Conclusion: This study demonstrates that lower level of maternal serum C3 in the early second trimester (14-20 weeks gestation) and abnormal increasing in uterine artery indices (PI and RI) are associated with developing pre-eclampsia several months later in pregnancy.