Abstract: Objective To explore the effect of paternal exposure to cigarette smoke prior to pregnancy on children's intelligence at 6 years old, so as to provide epidemiological evidence for prenatal and postnatal care services. Methods A total of 530 mother-child pairs were included in this study from the Shanghai-Minhang Birth Cohort Study (S-MBCS) established in 2012. Information on paternal exposure to cigarette smoke 3 months prior to pregnancy was obtained through a structured questionnaire at the first antenatal checkup. Intelligence of children at 6 years old was assessed using the Simplified Chinese Version of (the Wechsler Intelligence Scale for Children, Fourth Edition,WISC-Ⅳ). Multivariate linear regression model was used to analyze the effect of paternal cigarette smoke exposure prior to pregnancy on children's intelligence at 6 years old. Results After adjusting for covariates, paternal exposure to cigarette smoke prior to pregnancy was associated with a decrease of 2.83 points (95%CI:-5.51 to -0.16) of children's Full-Scale Intelligence Quotient (FSIQ). The effect of paternal smoking (OR=3.15, 95%CI:-6.32 to 0.03) was slightly stronger than that of paternal exposure to second-hand smoking (OR=2.62, 95%CI:-5.54 to 0.30). The effect of paternal smoking prior to pregnancy on children's FSIQ and Perceptual Reasoning Index (PRI) showed statistically significant dose-effect relationships (P_{for trend}<0.05). Children whose fathers smoked more than 5 cigarettes per day prior to pregnancy had a FSIQ decrease of 6.57 points (95%CI:-10.88 to -2.26) and a PRI decrease of 5.83 points (95%CI:-10.61 to -1.05). Besides, the sex and gestational weeks of children showed significant interactions with paternal exposure to cigarette smoke prior to pregnancy in the effects on children's intelligence (P_{for interaction}<0.05). The effects of paternal exposure to cigarette smoke prior to pregnancy on the intelligence of girls, or of children with less than 39 gestational weeks, were stronger. Conclusions Paternal exposure to cigarette smoke 3 months prior to pregnancy was associated with decreased children's intelligence at 6 years old. Our findings suggest that pre-pregnancy health guidance should strengthen the propaganda of husband's tobacco control before pregnancy, and both husband and wife should jointly assume the responsibility for prenatal and postnatal care.

Key words: prior to pregnancy, paternal exposure to cigarette smoke, children's intelligence, cohort study

摘要： 目的 评估孕前父亲烟草暴露对6岁儿童智力的影响,为指导优生优育服务提供循证依据。方法 本研究纳入2012年建立的上海闵行出生队列的530对母子,在孕妇建大卡时通过结构式问卷获得了孕前3个月父亲烟草暴露情况,在儿童6岁时利用第四版《儿童韦氏智力测试量表》中文版简版考察儿童智力水平。采用多因素线性回归模型分析孕前父亲烟草暴露对6岁儿童智力水平的影响。结果 调整协变量后,孕前父亲烟草暴露使儿童总智商下降2.83分(95%CI:-5.51～-0.16),其中孕前父亲吸烟的效应值(OR=3.15,95%CI:-6.32～0.03)略高于孕前父亲二手烟暴露(OR=2.62,95%CI:-5.54～0.30)。孕前父亲吸烟对儿童总智商和知觉推理的影响呈剂量反应关系(趋势检验P<0.05),父亲每天吸烟5支以上的儿童,总智商下降6.57分(95%CI:-10.88～-2.26),知觉推理下降5.83分(95%CI:-10.61～-1.05)。此外,儿童性别和胎龄与孕前父亲烟草暴露在对儿童智商的影响中表现出显著的交互作用(P<0.05),即父亲烟草暴露对女童、胎龄<39周的儿童的智力影响更强。结论 本研究发现孕前3个月父亲的烟草暴露与6岁儿童智力水平的下降有关,提示孕前健康指导应加强对备孕期间丈夫控烟的宣传,倡导夫妻双方共同承担起优生优育的责任。

关键词: 孕前, 父亲烟草暴露, 儿童智力, 队列研究