Orlebeke J F, Boomsma D I, Van Baal G C, Bleker O P
Department of Physiological Psychology, Free University, Amsterdam, Netherlands.
Early Hum Dev. 1994 Jun;37(3):161-6. doi: 10.1016/0378-3782(94)90074-4.
Since twins weigh about 20% less than singletons at birth, maternal smoking may be a more severe risk for them than for singletons. Therefore, the effect of maternal smoking during pregnancy on birth weight was investigated in a group of 5376 twins. All necessary information was collected by a questionnaire filled out by the mother of the twins. Gestational age explains more than 75% of the variance in birth weight. Other effects were tested with gestational age as a covariate. Apart from zygosity (DZ twins weigh more than MZ twins), birth order (first born twins weigh more than second born twins) and sex (boys weigh more than girls), there was a very significant birth weight reducing effect (more than 8%) maternal smoking as well as a significant influence of maternal age (young mothers give birth to smaller children). There were no interactions with maternal smoking.
由于双胞胎出生时的体重比单胎婴儿轻约20%，母亲吸烟对他们的风险可能比对单胎婴儿更严重。因此，在一组5376对双胞胎中研究了孕期母亲吸烟对出生体重的影响。所有必要信息均通过双胞胎母亲填写的问卷收集。孕周解释了出生体重差异的75%以上。以孕周作为协变量对其他影响因素进行了测试。除了合子性（异卵双胞胎比同卵双胞胎体重更重）、出生顺序（头胎双胞胎比二胎双胞胎体重更重）和性别（男孩比女孩体重更重）外，母亲吸烟对出生体重有非常显著的降低作用（超过8%），母亲年龄也有显著影响（年轻母亲所生孩子体重较轻）。未发现与母亲吸烟存在交互作用。
