الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Preeclampsia is a severe complication unique to human pregnancy with a worldwide incidence of 2–10%. Preeclampsia is one of the gestational hypertension diseases as (systolic blood pressure ≥140 mm Hg and diastolic blood pressure ≥90 mm Hg). It is defined as the new onset of hypertension and proteinuria after the 20th week of gestation. This intractable disease cause poor outcomes, such as intrauterine growth restriction, premature delivery, perinatal death, multiple organ disorder and neonatal complications. Preeclampsia is supposed to develop as a result of placental malperfusion, which results from insufficient remodeling of maternal spiral arteries.
Alpha-fetoprotein (AFP) is a glycoprotein produced by the secondary yolk sac, the fetal liver, and the gastrointestinal tract. Alpha-fetoprotein synthesis in the proliferating fetal liver increases through the 20th week of gestation and thereafter remains fairly constant until the 32nd week. The level of Alpha-fetoprotein is enhanced by the combination of fetal production, clearance through the fetal kidney, and by any perturbation of the placental interface between the fetus and the mother. Approximately 13% of women with elevated maternal serum alpha-fetoprotein developed pre-eclampsia compared with 1% of the women with normal maternal serum alpha-fetoprotein.
Alpha-fetoprotein is one part of the scanning of multiple serum markers, usually recommended to be done throughout 15 to 20 weeks of pregnancy. In most laboratories, using 2.0–2.5 multiples of the median (MoM) as the upper limit of normal maternal serum alpha-fetoprotein level, with a 5% false-positivity rate, the detection rate for anencephaly and spina bifida is 90% and 80%, respectively.
It has been hypothesized that a disruption in the maternal–fetal interface allows increased trasnfer of alpha-fetoprotein into the maternal circulation. Others suggest that elevated alpha-fetoprotein levels are a surrogate marker for abnormal implantation and placental malfunction that are the underlying pathologic mechanisms for many adverse obstetric outcomes.
Using a threshold value of two multiples of the median (MOM), elevated maternal serum alpha-fetoprotein in the mid-trimester has been shown to be associated with a 2.3 to 3.8 fold increased risk of developing pre-eclampsia.
Maternal serum alpha-fetoprotein level in the second trimester is still an important indicator for many pregnancy complications such as pre-eclampsia as it is an easily accessible and cheap test