A Study On The Relationship Between IGFs And Pregnancy Induced Hypertension And One Of It's Complications: Fetal Growth Restriction

Objective: Pregnancy Induced Hypertension (PIH) is a multisyste disorder of human pregnancy, occurring in 5-10% of all population births and represents the leading cause of both fetal and maternal morbidity and mortality in pregnancy. Symptoms of this syndrome: hypertension and impaired renal function appear during the second or third trimester of pregnancy. Despite intensive efforts to find mechanisms and markers induced PIH, no specific etioligical factor has been identified until now. Many hypotheses have been described, but none can be confirmed completely. Since Young put forward the uterine-placenta ischemia theory in 1918,it has been universally accepted. According to many schochers, PIH is a placental disease. The first stage is the process that affects the spiral arteries and results in a daficient blood supply to the placenta. The second stage encompasses the effects of the ensuring placental ischemia on both the fetus and the mother. Fetal growth restriction (FGR) is generally defined as the pathological restriction of fetal growth resulting in a fetus with birth weight below the 10th percentile for gestational age and it is ofen caused by preeclampsia. The mechanisms that contribute to postnatal growth failure following FGR are poorly understood. FGR may be a consequence of decreased uterine blood flow (uteroplacental insufficiency) and maternal and fetal hypoxia. Insulin-like growth factors regulate cellular proliferation,Differ entiation and function, and play an important role in placental development. The insulin-like growth factors are implicated in pre- and postnatal growth and development, and it is believed that alteration in their activity may contribute to FGR.Recently, a large number of epidemiolgic studies have been carried out and they demonstrate that IGFs is primarily involed the process of trophoblast invasion in maternal decidua and the spiral arteries. The aberrant trophoblast invasion to the spiral arteries result in placental dysfunction, which csuse the symptoms: edema,proteinuria,hypertension.Inaddition, impaired placental perfusion may be the csuse of placental dysfunction which may contribute to FGR.So we suspect that PIH and FGR may be the consequnce of the alteration of IGFs which cause to shallow placental implatation.Today ,to test whether IGFs are implicated in the pathogenesis of PIH and FGR,we measured maternal serum and umbilical serum levels of IGF-Ⅰ,IGF-Ⅱ in woman with PIH and in women throughout normal pregnancy.Methods:This study included 20 women with PIH(PIH group) ,26 women with PIH and FGR(PIH and FGR group) and 30 normotensive pregnant women(NT group)of similar gestation age.All women have had blood samples and umbilical cord blood samples taken when they are laboring.After verbal informed consent,venous blood was collected into a 10ml sterile plain tube without anticoagulant. The samples were allowed to clot before centrifugation. All fetus and placenta were weighted. All blood samples were stored at -20℃and measured at the same day to avoid interassay variation. Enzyme-linked immunosorbent assaya was used. The antibodies used in this procedure have no cross-reactivities with other cytokins. SPSS 11.5 was used, P﹤0.05 was considered statistically significant.Resuts: ⑴As compared with the NT group, the PIH group and PIH and FGR group had significantly( P﹤0.05) lower maternal IGF-Ⅰ(172.30±17.50ng/ml,170.27±27.96ng/ml vs 301.83±24.19ng/ml),umbilical IGF-Ⅰ(71.70±11.93ng/ml,55.34±14.03ng/ml vs 96.40±9.23ng/ml) and umbilical IGF-Ⅱ(1793.60±459.77ng/ml,916.69±161.93ng/ml vs 2067.17±360.49ng/ml). In the three groups, fetal birth weight and placental weight correlated positively with umbilical IGF-Ⅰ(r=0.870,p<0.01；r=0.710,p<0.01)and umbilical IGF-Ⅱ(r=0.840,p<0.01；r=0.650,p<0.01).The severity of PIH was dramatic decreasd in the concentrations of maternal and umbilical IGF-Ⅰ. In th two PIH group, the diastolic blood pressure, systolic blood pressure, mean arterial blood pressure(mABP), preteinuria and edema all had a...