الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Preeclampsia is a multi-system disorder during pregnancy which is characterized by new-onset hypertension (blood pressure is equal or more than 140/ 90 mm Hg, on two occasions, at least 6 hours apart) and proteinuria (protein excretion of 300 mg or more in a 24 hr. urine collection, or a dipstick of ≥ 1+) that develop after 20 weeks of gestation in previously normotensive women. The American College of Obstetrics and Gynecology revise the definition of preeclampsia in 2019 to exclude degree of proteinuria as a criterion of severe features.
It occurs in 3–8% of pregnancies.
According to the most recent analysis of the Centers for Disease Control and Prevention 9% of maternal deaths are directly due to preeclampsia and eclampsia ,so there is a continuous search for an ideal predictive test and preventive measure.
Pathology:
During normal placental implantation, cytotrophoblasts invade the maternal uterine spiral arteries that progresses deeper into the spiral artery to the level of the myometrium leading to extensive remodeling of the maternal spiral arterioles into high capacitance, high flow vessels, forming vascular sinuses at the fetal-maternal interface to provide nutrition to the fetus. In preeclampsia, cytotrophoblasts fail to invade the spiral artery which leads to incomplete remodeling of the spiral artery that causes narrow maternal vessels, and relative placental ischemia.
In literally located placenta the uterine artery nearer to the placenta has lower resistance than the opposite one and the uteroplacental blood flow needed are obtained primarily by one of the uterine arteries with little contribution from the other uterine artery through the collateral circulation. But in the centrally located placenta, both uterine arteries have similar resistance and the uteroplacental blood flow required are achieved by an equal contribution from both uterine arteries. The degree of collateral circulation is different from women to another and deficient contribution may facilitate the development of preeclampsia, IUGR, or both
This study was designed to demonstrate if placental laterality diagnosed by antenatal ultrasonography and abnormal uterine artery waveform as determined by antenatal Doppler can be used as a predictor for the development of preeclampsia.
This study was a prospective study that included 250 pregnant women attending to El bagour general hospital ante-natal outpatient clinic.An informed consent was taken from all participants after explanation of the nature and scope of the study.women who were pregnant women between 18:22 weeks gestation , singleton fetus , intact membrane , normotensive at time of joining the study and without any high risk factor were included in the study. But cases with chronic or essential hypertension, thyrotoxicosis, renal disease, diabetes mellitus, severe anemia, connective tissue disorder, positive lupus anticoagulant, anticardiolipin antibodies, rh incompatibility ,twin pregnancy , history of smoking and with any congenital uterine anomalies were excluded from it For every case the following were recorded:-Placental location was determined by ultrasound at 18 to 22weeks.The placenta was classified as central when it was equally distributed between the right and left side of uterus irrespective of anterior, posterior, or
Summary
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fundal position. When 75 % or more of the placental mass was located at one side of the midline of uterine cavity, it considered lateral placenta.
- Color Doppler was done to all cases at18-22 week of gestation to find out the uterine artery resistance index and abnormal notching in Doppler waveform. Doppler insonation of the uterine artery is at the level of its apparent crossover with the external iliac artery. Using this method, the probe is positioned approximately 2-3 cm inside the iliac crests and then directed toward the pelvis and the lateral side of the uterus. Color flow Doppler is used to identify each uterine artery. Pulsed wave Doppler is applied approximately 1 cm above the point at which the uterine artery crosses over the external iliac artery. This ensures that Doppler velocities are obtained from the main uterine artery trunk. It was done in the ipsilateral side of placenta. Uterine artery resistance index of more than 0.56 and presence of protodiastolic notch in the placental ipsilateral side in uterine were artery were taken as significant
All cases were followed till delivery for occurrence of signs and symptoms of preeclampsia. All cases before 40 weeks who developed early onset and late onset preeclampsia were included in the final analysis.
It has been concluded that lateral placenta can be used as a predictor marker for preeclampsia, and if all patients with lateral placenta undergo color Doppler, preeclampsia can be predicted more accurately.
Receiver Operating characteristic (ROC) curves were produced in an attempt to show the ability of uterine artery Doppler in laterally located placenta to predict the occurrence of Preeclampsia with accuracy of 68.72% (p value =0.001).