Ronnenberg Alayne G, Goldman Marlene B, Chen Dafang, Aitken Iain W, Willett Walter C, Selhub Jacob, Xu Xiping
Departments of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA.
Am J Clin Nutr. 2002 Dec;76(6):1385-91. doi: 10.1093/ajcn/76.6.1385.
The associations between homocysteine, B vitamin status, and pregnancy outcomes have not been examined prospectively.
We assessed the associations of preconception homocysteine and B vitamin status with preterm birth and birth of low-birth-weight (LBW) and small-for-gestational-age (SGA) infants in Chinese women.
This was a case-control study of women aged 21-34 y. Preterm cases (n = 29) delivered living infants at <37 wk gestation; term controls (n = 405) delivered infants at > or =37 wk. LBW cases (n = 33) had infants weighing <2500 g; normal-birth-weight controls (n = 390) had infants weighing > or =2500 g. SGA cases (n = 65) had infants below the 10th percentile of weight-for-gestational-age; appropriate-for-gestational-age controls (n = 358) had infants above this cutoff. Nonfasting plasma concentrations of homocysteine, folate, and vitamins B-6 and B-12 were measured before conception.
Elevated homocysteine (> or =12.4 micro mol/L) was associated with a nearly 4-fold higher risk of preterm birth (OR: 3.6; 95% CI: 1.3, 10.0; P < 0.05). The risk of preterm birth was 60% lower among women with vitamin B-12 > or =258 pmol/L than among vitamin B-12-deficient women (OR: 0.4; 95% CI: 0.2, 0.9; P < 0.05) and was 50% lower among women with vitamin B-6 > or =30 nmol/L than among vitamin B-6-deficient women (OR: 0.5; 95% CI: 0.2, 1.2; NS). Folate status was not associated with preterm birth, and homocysteine and B vitamin status were not associated with LBW or SGA status.
Elevated homocysteine and suboptimal vitamin B-12 and B-6 status may increase the risk of preterm birth. These results need to be confirmed in larger prospective studies.
同型半胱氨酸、B族维生素状态与妊娠结局之间的关联尚未进行前瞻性研究。
我们评估了中国女性孕前同型半胱氨酸和B族维生素状态与早产、低出生体重（LBW）儿及小于胎龄（SGA）儿出生之间的关联。
这是一项针对21 - 34岁女性的病例对照研究。早产病例（n = 29）在妊娠<37周时分娩活婴；足月对照（n = 405）在妊娠≥37周时分娩婴儿。低出生体重病例（n = 33）的婴儿体重<2500 g；正常出生体重对照（n = 390）的婴儿体重≥2500 g。小于胎龄病例（n = 65）的婴儿体重低于胎龄体重的第10百分位数；适于胎龄对照（n = 358）的婴儿体重高于此临界值。在受孕前测量非空腹血浆中同型半胱氨酸、叶酸、维生素B - 6和维生素B - 12的浓度。
同型半胱氨酸水平升高（≥12.4 μmol/L）与早产风险增加近4倍相关（比值比：3.6；95%可信区间：1.3, 10.0；P < 0.05）。维生素B - 12≥258 pmol/L的女性早产风险比维生素B - 12缺乏的女性低60%（比值比：0.4；95%可信区间：0.2, 0.9；P < 0.05），维生素B - 6≥30 nmol/L的女性早产风险比维生素B - 6缺乏的女性低50%（比值比：0.5；95%可信区间：0.2, 1.2；无统计学意义）。叶酸状态与早产无关，同型半胱氨酸和B族维生素状态与低出生体重或小于胎龄状态无关。
同型半胱氨酸水平升高以及维生素B - 12和B - 6状态欠佳可能会增加早产风险。这些结果需要在更大规模的前瞻性研究中得到证实。
