Martin T R, Bracken M B
Am J Epidemiol. 1986 Oct;124(4):633-42. doi: 10.1093/oxfordjournals.aje.a114436.
In a prospective study of 3,891 antenatal patients at Yale-New Haven Hospital between 1980 and 1982, one fourth (23.6%) had not smoked cigarettes during pregnancy but had been exposed to sidestream smoke for at least two hours per day. Among the nonsmokers, passive smoke exposure was significantly related to delivering a low birth weight (less than 2,500 g) newborn. This relation only occurred in term (greater than or equal to 37 weeks) deliveries. Compared with unexposed women, the relative risk of low birth weight after adjustment for confounding factors was 2.17 (95% confidence interval (CI) = 1.05-4.50). Those exposed to passive smoke delivered infants 24 g lighter on average. There was no additive effect of passive smoking on smokers themselves. Repeating the analysis on all women with term deliveries, therefore, resulted in a slightly diminished risk of low birth weight due to passive smoking of 1.52 (95% CI = 0.90-2.56). The risk of low birth weight at term due to direct cigarette smoking was 3.54 (95% CI = 1.62-7.71). Gestational age was unrelated to passive smoking, which appears to exert its effect primarily through growth retardation in term newborns.
在1980年至1982年间对耶鲁-纽黑文医院3891名产前患者进行的一项前瞻性研究中，四分之一（23.6%）的患者在孕期不吸烟，但每天至少有两小时暴露于侧流烟雾中。在不吸烟的人群中，被动吸烟与分娩低体重（低于2500克）新生儿显著相关。这种关系仅出现在足月（大于或等于37周）分娩中。与未暴露的女性相比，在对混杂因素进行调整后，低体重出生的相对风险为2.17（95%置信区间（CI）=1.05 - 4.50）。暴露于被动吸烟的女性所生婴儿平均轻24克。被动吸烟对吸烟者自身没有叠加效应。因此，对所有足月分娩的女性重复进行分析，因被动吸烟导致低体重出生的风险略有降低，为1.52（95%CI = 0.90 - 2.56）。直接吸烟导致足月低体重出生的风险为3.54（95%CI = 1.62 - 7.71）。孕周与被动吸烟无关，被动吸烟似乎主要通过足月新生儿的生长迟缓发挥作用。
