Thrombophilia and pregnancy complications

OBJECTIVE: This systematic review examines the strength of the association between thrombophilia and recurrent pregnancy loss and other serious obstetric complications.Study design Electronic databases and manual bibliography searches were used to identify studies evaluating the association between thrombophilia and pregnancy loss, preeclampsia, fetal growth retardation, and placental abruption. RESULTS: Thrombophilic disorders are associated with an increased risk of fetal loss in the majority of case control and cohort studies. The risk is increased throughout pregnancy, but may be higher in the second and third trimester. The common pathologic finding of placental infarction suggests unexplained fetal loss may result from uteroplacental insufficiency and thrombosis. Thrombophilic disorders are not consistently associated with preeclampsia, fetal growth retardation, or placental abruption. Preliminary data suggest prophylactic anticoagulation may improve outcome in thrombophilic women with unexplained recurrent fetal loss. CONCLUSION: Women with thrombophilia have an increased risk of pregnancy loss and possibly other serious obstetric complications, although definition of the magnitude of risk will require prospective longitudinal studies. Preliminary data suggesting prophylactic anticoagulation may improve gestational outcome provide a rationale for prospective randomized trials in thrombophilic women with unexplained recurrent fetal loss.     

Increased fetal DNA in the maternal circulation in early pregnancy is associated with an increased risk of preeclampsia

OBJECTIVE: The aim of our study was to determine if fetal DNA is present in the maternal circulation in early pregnancy before the clinical manifestation of preeclampsia, and if this could be predictive of the development of preeclampsia. STUDY DESIGN: Blood were obtained from patients attending for a first antenatal visit. Cases were asymptomatic women who subsequently developed preeclampsia matched to control women for parity and gestational age. Real-time polymerase chain reaction (PCR) using TaqMan primers and probes directed against SRY gene sequences quantified fetal DNA in the maternal circulation. RESULTS: There were 88 cases of women with preeclampsia and 176 control women, both sampled at a mean gestation (+/-SD) of 15.7 +/- 3.6 weeks. The presence of fetal DNA in the maternal circulation in early pregnancy is associated with an 8-fold increased risk of developing preeclampsia. CONCLUSION: Increased fetal DNA is present in the maternal circulation in early pregnancy in women who subsequently develop pre-eclampsia and there appears to be a graded response between the quantity of fetal DNA and the risk of developing pre-eclampsia.     

Is early-pregnancy proteinuria associated with an increased rate of preeclampsia in women with pregestational diabetes mellitus?

OBJECTIVE: The purpose of this study was to determine whether the rate of preeclampsia in pregnant diabetic women is increased in those women with early-pregnancy proteinuria of 190 to 499 mg/24 hours compared with women with proteinuria of <190 mg/24 hours. STUDY DESIGN: Secondary analysis was performed with relevant data from 194 pregnant women with type 1 and type 2 diabetes mellitus whose condition required insulin and who were enrolled previously in a multicenter trial of low-dose aspirin for the prevention of preeclampsia. The women were assigned to 1 of 3 groups, based on the level of proteinuria at enrollment (13-26 weeks of gestation). Group 1 comprised women with <190 mg protein/24 hours (n=94); group 2 comprised women with 190 to 499 mg protein/24 hours (n=35); and group 3 comprised women with >/=500 mg protein/24 hours (n=65). The rate of preeclampsia, according to strict predefined criteria, was then determined. RESULTS: The rate of preeclampsia was not increased statistically significantly in patients with early-pregnancy proteinuria of 190 to 499 mg/24 hours (7/35 women; 20%) when compared with women with proteinuria of <190 mg/24 hours (16/94 women; 17%). CONCLUSION: We did not find an increased rate of preeclampsia in women with pregestational diabetes mellitus with early-pregnancy proteinuria of 190 to 499 mg/24 hours when compared with women with pregestational diabetes mellitus with proteinuria of <190 mg/24 hours.     

Different levels of platelet activation in preeclamptic, normotensive pregnant, and nonpregnant women

OBJECTIVE: The aims of our study were to determine the basal platelet activation state in women with preeclampsia compared with normotensive pregnant women and nonpregnant women and to investigate the platelet reactivity on in vitro stimulation with adenosine diphosphate or thrombin receptor activation peptide. STUDY DESIGN: Platelet expression of CD61 (fibrinogen receptor), CD42a (von Willebrand factor receptor), CD62P (P-selectin), CD63 (Glycoprotein 53), and PAC-1 binding (activated fibrinogen receptor) were determined in 20 pairs of women with preeclampsia/normotensive pregnant women and in 12 nonpregnant women, with the use of flow cytometry. RESULTS: Basal platelet expression of CD61, CD42a and CD62P, and adenosine diphosphate-stimulated CD62P expression were increased in women with preeclampsia compared with normotensive pregnant women. Platelets from women with preeclampsia and normotensive pregnant women differed from platelets from nonpregnant women by expressing higher basal CD63 levels and being more responsive to in vitro agonist stimulation, which was demonstrated by increased expression of CD61, CD62P, and CD63. CONCLUSION: This study supports the notion that platelets are important in the pathophysiologic condition of preeclampsia.     

Effect of varying doses of fentanyl with low dose spinal bupivacaine for caesarean delivery in patients with pregnancy-induced hypertension

The purpose of this study was to evaluate haemodynamic stability, perioperative analgesia and neonatal outcome following intrathecal 0.5% bupivacaine 7.5 mg with varying doses of fentanyl, in parturients with pregnancy-induced hypertension. Forty-five parturients with pregnancy-induced hypertension scheduled for caesarean section were randomly allocated to receive 7.5 mg bupivacaine with saline 1 mL (group B), fentanyl 10 microg (group Bf10) or fentanyl 20 microg (group Bf20) intrathecally. Heart rate, blood pressure, and sensory block were recorded at regular intervals. Pain, nausea, vomiting, pruritus or any other side effects were sought. Neonatal outcome was assessed using Apgar score and umbilical artery blood gas analysis. Adequate surgical anaesthesia was established in all three groups. There was a statistically significant fall in mean arterial pressure in all three groups within 4-6 min of subarachnoid block (P<0.05), but the decrease in MAP was <20% of baseline in all three groups. Pain and discomfort during surgery were experienced more frequently in group B than in groups Bf10 and Bf20 (P<0.05). Duration of postoperative analgesia was significantly longer in group Bf20 (5.55+/-1.18 h) than in group Bf10 (3.97+/-2.12 h) and group B (3.27+/-1.8 h) (P<0.05). Neonatal outcome was similar in the three groups. Intrathecal fentanyl with low dose bupivacaine provides good surgical anaesthesia and prolongs the duration of analgesia without haemodynamic or neonatal compromise in patients with pregnancy-induced hypertension undergoing caesarean delivery.     

Fetoplacental vascular tone is modified by magnesium sulfate in the preeclamptic ex vivo human placental cotyledon

OBJECTIVE: The purpose of this study was to evaluate fetoplacental vascular tone and response to a vasoconstrictor in placentas of preeclamptic and normotensive pregnancies with and without the presence of magnesium sulfate. STUDY DESIGN: Two cotyledons from each placenta were selected from preeclamptic (n=8) and normotensive (n=7) pregnancies. In one cotyledon from each pair, the maternal circuit was perfused with magnesium sulfate. The fetal arteries were injected sequentially with angiotensin II (10(-10)mol and 10(-11.5) mol). Perfusion pressures and response to angiotensin II were compared, with regard to preeclampsia and exposure to magnesium sulfate. RESULTS: Perfusion pressure was higher in preeclamptic placentas, compared with normotensive placentas (30.4 mm Hg vs 24.4 mm Hg, P=.02). There was a decrease in perfusion pressure with exposure to magnesium sulfate in preeclamptic placentas (22.5 mm Hg, P<.01), but not in normotensive placentas. Fetoplacental vascular response to angiotensin II was not affected by preeclampsia or magnesium sulfate. CONCLUSION: In placentas from preeclamptic pregnancies there is increased fetoplacental perfusion pressure, which decreases with exposure to sulfate.     

ROCKⅡ与子痫前期发病的关系

为了解ROCKⅡ与子痫前期发病的关系,查阅国内外文献并对文献进行整理,发现ROCKⅡ在子痫前期发病过程中起一定作用,现就Rho/ROCK信号传导通路与妊娠的关系做一综述。     

白血病抑制因子在子痫前期患者胎盘组织中的表达

目的:测定白血病抑制因子(LIF)在子痫前期患者胎盘组织中的表达,探讨其在妊娠高血压发病中的作用。方法:采用免疫组化技术-链霉菌抗生物素蛋白-过氧化酶连接(SP)法对在正常妊娠(正常妊娠组)、子痫前期(轻度子痫前期组和重度子痫前期组)孕妇胎盘组织中LIF的表达进行组织学定位和半定量分析。结果:3组孕妇胎盘组织中LIF均呈现阳性表达,阳性染色主要位于滋养细胞胞质中,胞核无明显着色。轻度子痫前期组和重度子痫前期组分别与正常妊娠组比较,胎盘组织的染色强度及范围显著减弱,差异有统计学意义(P<0.01),而轻度子痫前期组和重度子痫前期组的胎盘组织染色范围和强度比较,差异无统计学意义(P>0.05)。结论:LIF对维持正常妊娠有一定的保护作用,LIF分泌或调控异常,影响了滋养细胞的浸润能力,导致病理妊娠,在胎盘组织中的低表达,参与了子痫前期发病机制。     

子痫前期患者胎盘整合素α1与β1及肿瘤坏死因子α的表达及其临床意义

目的:探讨整合素α1、β1与肿瘤坏死因子α在子痫前期患者胎盘组织中的表达及其临床意义。方法:采用免疫组化SP法检测50例子痫前期患者(轻度20例,重度30例)胎盘组织中整合素α1、β1及肿瘤坏死因子α的表达;40例正常孕妇为对照组。结果:子痫前期组胎盘绒毛滋养细胞及蜕膜细胞整合素α1、β1的阳性表达率均明显低于对照组(整合素α1:58.00%和80.00%,P<0.05,整合素β1:56.00%和76.50%,P<0.05);肿瘤坏死因子α的阳性表达率明显高于对照组(肿瘤坏死因子α:80.00%和32.00%,P<0.05)。子痫前期组轻、重度患者整合素α1、β1及肿瘤坏死因子α表达的阳性率分别为整合素α1:75.00%和46.67%,整合素β1:75.00%和43.33%,并随病情程度加重而降低;肿瘤坏死因子α:65.00%和90.00%,并随病情程度加重而升高。整合素α1、β1的表达与胎盘重量及新生儿体重呈正相关。结论:胎盘表达整合素α1、β1与肿瘤坏死因子α异常引起滋养细胞浸润不足,可能是子痫前期的发病因素之一。     

子前期胎盘组织差异表达基因PP2ACβ的初步研究

目的寻找并克隆子前期胎盘组织高表达基因蛋白磷酸酶2A催化亚基β(PP2ACβ),研究其mR-NA及蛋白水平的表达,探讨其在子前期中的作用。方法标本取自2004年5月至2004年12月天津中心妇产科医院重度子前期及正常孕妇各30例。应用荧光mRNA差异显示技术(FDD)发现并克隆子前期胎盘组织差异表达的基因PP2ACβ,进一步应用半定量RT-PCR及免疫组化技术分析差异表达基因PP2ACβmRNA及其蛋白水平PP2A的表达。结果通过FDD发现PP2ACβ基因在子前期胎盘组织中高表达,半定量RT-PCR证实PP2ACβmRNA在子前期胎盘组织中的表达(0.888±0.104)高于正常胎盘组织(0.692±0.099),差异有统计学意义(P<0.05),免疫组化验证其蛋白水平PP2A的表达(0.14±0.02)亦高于正常(0.12±0.02),差异有统计学意义(P<0.05)。结论FDD可有效用于筛选子前期胎盘组织差异表达基因;PP2A可能通过促进胎盘滋养层细胞的凋亡及阻碍血管生成而参与子前期的发病。