Werler M M, Louik C, Shapiro S, Mitchell A A
Slone Epidemiology Unit, Boston University School of Public Health, Brookline, MA 02146, USA.
JAMA. 1996 Apr 10;275(14):1089-92. doi: 10.1001/jama.1996.03530380031027.
To examine the relation between prepregnant weight and the risk of neural tube defects (NTDs).
Data were collected from 1988 to 1994 in a case-control surveillance program of birth defects.
Study subjects were ascertained at tertiary care centers and birth hospitals in the greater metropolitan areas of Boston, Mass, and Philadelphia, Pa, and in southeastern Ontario.
Cases were 604 fetuses or infants with an NTD identified within 6 months of delivery. Controls were 1658 fetuses or infants with other major malformations identified within 6 months of delivery. For 1992 to 1994, there were 93 control infants without major malformations.
Relative risk of NTDs in infants or fetuses for different maternal weights.
Relative to women who weighed 50 to 59 kg, risk of NTDs increased from 1.9 (95% confidence interval [CI], 1.2 to 2.9) for women weighing 80 to 89 kg to 4.0 (95% CI, 1.6 to 9.9) for women weighing 110 kg or more. When women were classified according to daily intake above or below the recommended level of 400 micrograms of folate, approximate threefold increases in risk were estimated for the heaviest weights in both groups. Intakes of 400 micrograms of folate or more reduced risk of NTDs by 40% among women weighing less than 70 kg, but no risk reduction was observed among heavier women.
The risk of NTDs increased with increasing prepregnant weight, independent of the effects of folate intake.
研究孕前体重与神经管缺陷（NTDs）风险之间的关系。
数据收集于1988年至1994年的一项出生缺陷病例对照监测项目。
研究对象来自马萨诸塞州波士顿和宾夕法尼亚州费城大都市区以及安大略省东南部的三级护理中心和妇产医院。
病例为604例在分娩后6个月内确诊为NTDs的胎儿或婴儿。对照为1658例在分娩后6个月内确诊为其他重大畸形的胎儿或婴儿。1992年至1994年，有93例对照婴儿无重大畸形。
不同孕妇体重的胎儿或婴儿患NTDs的相对风险。
与体重在50至59千克的女性相比，体重在80至89千克的女性患NTDs的风险从1.9（95%置信区间[CI]，1.2至2.9）增加到体重在110千克及以上女性的4.0（95%CI，1.6至9.9）。当根据每日叶酸摄入量高于或低于推荐水平400微克对女性进行分类时，两组中体重最重的女性患NTDs的风险估计增加约三倍。体重小于70千克的女性摄入400微克及以上叶酸可使NTDs风险降低40%，但体重较重的女性未观察到风险降低。
孕前体重增加，NTDs风险增加，与叶酸摄入量的影响无关。
