A NESTED CASE CONTROL STUDY EVALUATING THE ASSOCIATION BETWEEN THE FACTOR V LEIDEN GENOTYPE AND ADVERSE PREGANCY OUTCOME

普通人群中有1/20存在因子V Leiden基因突变。最近的研究表明，因子V莱顿基因突变与不良妊娠结局之间存在关联。目前建议，有反复妊娠流产史的妇女，包括妊娠中期或晚期宫内死亡的妇女，应筛查因子V莱顿突变。目前正在进行对照试验，评估筛查呈阳性的妇女接受抗凝治疗的疗效。然而，目前不建议进行人群筛查，因为我们不知道因子V莱顿基因突变对没有不良妊娠结局病史的妇女的意义。为什么一些携带因子V莱顿突变的女性会经历反复的妊娠丢失，而其他女性没有，这个问题仍然没有答案。这项研究的主要目的是确定在25,000名孕妇队列中，凝血因子V莱顿的母体和/或胎儿基因型是否影响妊娠早期和中期流产的风险。这一领域进一步研究的目的是根据遗传、获得性和环境亲血栓风险因素的组合，确定怀孕中期或晚期胎儿丢失风险增加的一组妇女，她们可能受益于预防性治疗和抗凝治疗。

The factor V Leiden gene mutation is present in 1 in 20 of the general population. Recent studies suggest an association between the factor V Leiden gene mutation and adverse pregnancy outcomes. It is currently recommended that women with a history of recurrent pregnancy loss, including a second or third trimester intrauterine death should be screened for the factor V Leiden mutation. Controlled trials are currently underway assessing efficacy of treatment with anticoagulaton therapy for women who screen positive. However, population screening is currently not recommended because we do not know the significance of a factor V leiden gene mutation for women without a previous history of adverse pregnancy outcome. The question of why some women with a factor V Leiden mutation experience recurrent pregnancy loss whereas other women do not remains unanswered. The primary aim of this study is to determine whether the maternal and- or fetal genotype for factor V Leiden influences the risk of first and second trimester miscarriage within a cohort of 25,000 pregnant women. The aim of further research in this area is to identify a subset of women at increased risk of a second or third trimester fetal loss, based on a combination of genetic, acquired and environmental thrombophilic risk factors, who may benefit from prophylactic treatment with anticoagulation therapy.