COMBINED MATERNAL SERUM C3 ACTIVATION AND UTERINE ARTERY DOPPLER AT 14 – 20 WEEKS AS PREDICTORS FOR PRE-ECLAMPSIA IN PRIMIGRAVIDA

Abstract

Preeclampsia is a multisystem disorder that affects 2-8% of all pregnancies and is a major contributor to maternal and perinatal morbidity and mortality. It is characterized by new onset of hypertension and proteinuria after 20 weeks of gestation. Various publications showed that in first trimester screening, Doppler examination of the uterine arteries identified a certain percentage of pregnant women with elevated pulsatility, resistance index (PI and RI respectively) and the presence of early diastolic notch that later develop preeclampsia. The syndrome of pre-eclampsia is associated with dysregulation of the immune system. Indeed, a significant link between inflammations related to complement activation in early human pregnancy with the development of pre-eclampsia later in pregnancy. Evidence from murine studies also suggests an important role for complement activation in intrauterine fetal death and intrauterine growth restriction. The aim of this study was to assess the efficacy of C3 estimation and measurement of uterine artery Doppler indices before 20 weeks of pregnancy for prediction of preeclampsia.  132 The current prospective study was conducted at Ain-Shams University Maternity Hospital on a total of 140 pregnant women attending to the antenatal care unit at 14 to 20 weeks gestation during the period from September 2013 to July 2014. Normotensive nulliparous patients with singleton alive fetus and absent congenital anomalies were included in this study while patients with collagen diseases, essential hypertension, causes of secondary hypertension e.g.: renal disease, dead fetus, diabetes mellitus, congenital fetal malformations or multiparity were excluded from the study. After approval of the ethical committee, each procedure was explained in detail for each patient. All recruited patients were given an informed written consent. All patients were subjected to careful detailed history taking and careful detailed general and obstetric examination. Transabdominal ultrasound was done for each patient at first visit to assess the uterine artery using Medisone X6 ultrasound machine equipped with C 3-7 Mhz convex probe by the same operators. All pregnancies were dated by bi-pareital and femur length measurements. At the ultrasound examination, a mid-sagittal section of the uterus was obtained, and the cervical canal was identified.  133 Color Doppler imaging was used to identify the uterine artery as it turned cranially to make its ascent to the uterine body. Measurements were then taken at this point, before the uterine artery branched into the arcuate arteries. Pulsed-wave Doppler was used to obtain the presence of a protodiastolic notch, the resistance index (RI) and the pulsatility index (PI). C3 levels were assessed at first visit by Human Complement C3 „Nl‟ Bindarid Radial Immunodiffusion kit which was designed for the in vitro measurement of human C3 in serum using fresh or deep frozen serum samples. Blood samples were collected by venepuncture, allowed to clot naturally and the serum separated as soon as possible to prevent haemolysis.The serum may be stored at 2- 8oC for up to 48 hours prior to assay, or for prolonged storage, alliquoted and kept at –20oC or below. 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.