18周内孕妇血清同型半胱氨酸、叶酸及维生素B_(12)水平对妊娠结局的影响

Influence of serum levels of homocysteine,folate and vitamin B_(12) before 18 weeks pregnant on pregnancy outcomes

目的观察18周内孕妇血清同型半胱氨酸、叶酸及维生素B12水平对产后胎盘重量、胎儿体重、早产结局的影响。方法我院2006年6至2011年12月孕龄小于18周的孕妇806例,抽血检测血清标志物同型半胱氨酸、叶酸及维生素B12的含量,生产后记录妊娠结局,并使用线性回归和Logistic回归分析孕早期血清标志物与不良妊娠结局的关系。结果高血清同型半胱氨酸水平(>8.3μmol/L)孕妇的胎盘重量比低同型半胱氨酸水平(<8.3μmol/L)孕妇平均轻30 g(P<0.001),新生儿体重轻110 g(P<0.001);而低叶酸水平(<9.2 nmol/L)孕妇的胎盘重量比高叶酸水平(>9.2 nmol/L)孕妇平均轻26 g(P<0.001),新生儿体重轻125 g(P<0.001),早产风险升高(OR 2.2,P=0.002),子痫前期风险上升(OR 2.1,P=0.04)。维生素B12的血清含量对妊娠结局无显著影响。结论血清同型半胱氨酸的含量升高,血清叶酸的含量降低,胎盘重量和新生儿体重会降低,早产和前期子痫的发生风险增高。

Objective To investigate whether or not there is an association of serum concentrations of homocysteine, folate and vitamin B12 in early pregnancy with placental weight, baby birth weight and adverse pregnancy outcomes. Methods We conducted a cohort study including 806 early pregnant women （gestational age 〈 18 weeks） in our hospital. Serum concentrations of homocysteine, folate and vitamin B12 were examined, and the characteristics like height, body weight, alcohol use was reeoded. We used multivariate re- gression analyses to analyze association of these biomarkers with adverse birth outcomes. Results The placental weight and baby body weight in pregnant women with high serum homocysteine concentration （ 〉 8.3 μmol/L） were 30g and 110g lower than that in pregnant women with low serum homocysteine concentration （ 〈 8.3 μmol/L）, respectively （ both P 〈 0. 001 ）. Whereas, the placental weight and baby body weight in pregnant women with low serum folate concentration （ 〈 9. 2 nmol/L） were 26 g and 125 g lower than that in pregnant women with high serum folate concentration （〉 9.2 nmol/L）, respectively （both P 〈 0.001 ）. The risks of premature birth （OR 2.2,P = 0.002） and pre-eclampsia （OR 2.1 ,P = O. 04） were increased compared with the highest quintile. No associations were found with vitamin Bl2. Conclusions Higher homocysteine and lower folate concentrations in early pregnancy are associated with lower placental weight and baby birth weight, and higher risk of adverse pregnancy outcomes.