Introduction : Preeclampsia is a major cause of maternal and perinatal mortality and morbidity worldwide.It is a multi - system disease of the vascular endothelium, with vasoconstriction, renal vascular damage and abnormal coagulation.In the placental bed fibrin and platelet deposition, thrombosis, and infarction occur and result in reduced placental perfusion. Altered coagulability may be important in the pathogenesis of preeclampsia.Lipo-protein (a), has been found to enhance blood coagulation .Objective : To determine circulating levels of cholestreol, triglycerides, HDL, LDL, and Lipoprotein (a) in sera of patients with severe pre-eclamptic toxemia on two occasions (32 -34 weeks gestatio),correlate the biochemical data,with concomitant determined umbilical artery resistance index using duplex Doppler;with the aim of finding a causal relationship between lipid profile and vascular flow.Study Design : The present study was carried out on 19 pregnant women with severe PIH (severity was determined by BP level of > 160/110 or proteinuria +++), compared with 17 normal pregnant women as a control group.The PIH group patient were examined at 2 occasion 1st at +32 weeks gestation and 2nd +10 to 14 days later.while the control group (normal) were examined at the mean fetal age + 33weeks.Doppler waveform assessment was done to pick up the pathological waveform in umbilical artery and correlating the results to lipid profile and fetal weight.Results : The present study observed elevated lipoprotein (a) levels in preeclampsia and associated with the severity of the disease. Whether elevated lipoprotein (a) is a causative factor for preeclampsia lipoprotein (a) may be an additional risk marker for preeclampsia and may be useful in distinguishing women with preeclampsia from normal pregnancy. Recmendation : Prospective studies of lipoprotein (a) levels in pregnant women and in vitro experiments of the effects of lipoprotein (a) on placental vessel formation and “atherosis” changes are needed to establish the causal relationship between elevated lipoprotein (a) and preeclampsia.