胎儿期凝血因子Ⅷ、Ⅸ、Ⅺ的生成趋势

Development of human coagulation factor Ⅷ,Ⅸ,Ⅺ in the healthy fetuses

目的分析人类胎儿期三种凝血因子的生成趋势及正常范围,以探讨凝血因子活性测定对血友病胎儿的产前诊断价值。方法检测327例18周以上胎儿脐带血中凝血因子Ⅷ、Ⅸ、Ⅺ(FⅧ、FⅨ及FⅪ)的活性,分析胎儿期三种凝血因子的增长趋势及正常范围。统计学方法采用SPSS10.0软件探索性分析、相关分析及t检验。结果①妊娠中晚期胎儿FⅧ的活性已超过30%,95%置信区间为47.57%~50.55%;FⅨ的活性在20%以下,95%置信区间为10.37%~11.60%;FⅪ的活性在40%以下,95%置信区间为22.86%~25.35%。②FⅧ、FⅨ、FⅪ活性与胎龄均呈正相关关系。③胎儿FⅧ、FⅨ的活性在34周后才出现明显增长;FⅪ的活性随胎龄的增加逐渐上升,但上升的幅度无统计学差异。结论①20周以上正常胎儿的FⅧ活性已达30%以上,FⅧ活性测定结合基因检测可能降低血友病甲胎儿产前诊断的误诊率和漏诊率。②胎儿期FⅨ、FⅪ的活性均较低下,尚不适合于作为血友病乙、血友病丙产前诊断的指标。③胎儿期凝血因子活性的增长趋势与胎龄成正比。

ObjectiveTo study the development of human coagulation factor Ⅷ,Ⅸ,Ⅺ(FⅧ,FⅨ,FⅪ) in the healthy fetuses and the value of coagulation factors determination in the diagnosis of hemophilia. MethodsThe umbilical cord blood of 327 fetuses between 18 and 37 weeks of gestational age was collected by cordocentesis.The Level of coagulation factor Ⅷ,Ⅸ and Ⅺ were determined.Results① During the second and third trimester,the activity of FⅧ was greater than 30% of adult,the 95 percent confidence intervals were 47.57 to 50.55 percent.The activity of FⅨ and FⅪ were lower than 20% and 40% of adult,respectively.② The coagulation factor activity increased with the gestational age.③ The coagulation factor Ⅷ and Ⅸ increased sharply after 34 weeks of gestational age.The coagulation factor Ⅺ increased with the gestational age,but no significant difference was found.Conclusion① The FⅧ activity of normal fetuses of greater than 20 weeks of gestation age was higher than 30% of adult.Determination of FⅧ activity of umbilical cord blood combined with FⅧ gene detection might reduce the rate of misdiagnosis and missed diagnosis of hemophilia A.② The FⅨ and FⅪ activety are low in the healhty fetuses.The determination of FⅨ and FⅪ activety might not be helpful in the diagnosis of hemophilia B and C.③ The coagulation factor activity increased with the gestational age.