Academic Child Health, University of Aberdeen, Aberdeen AB25 2ZG, UK.
Thorax. 2010 Mar;65(3):235-40. doi: 10.1136/thx.2009.123232.
Maternal smoking in pregnancy is associated with reduced birth weight and childhood lung function. This study determined when maternal smoking first influences fetal growth and how this relates to childhood respiratory outcomes.
A longitudinal cohort of 1924 pregnant women was recruited. Fetal ultrasound measurements at 11 weeks (crown-rump length, CRL) and at 20 weeks gestation (femur length, FL, and biparietal diameter, BPD) and birth measurements were recorded. Childhood respiratory symptoms and spirometry were ascertained.
Of the 1924 original study participants, fetal size was determined in 903 in the first trimester, 1544 in the second trimester and at term in 1737 infants. Maternal smoking when first pregnant was reported in 593 (31%) and was not associated with reduced CRL. There was an inverse exposure-response relationship between cigarette consumption and FL (mean reduction in lowest compared with highest tertile 0.91 cm, p=0.033). Birth weight and length of those born to mothers who did (n=331) and did not (n=56) reduce cigarette consumption were similar and reduced compared with 186 infants whose mothers quit during the first trimester (p < or = 0.020). Children of mothers who continued smoking had increased wheeze at age 2 years (OR 1.58, p=0.017) and GP visits with wheeze at age 5 years (OR 2.18, p=0.030) and mean reduction in forced expiratory volume in 1 s of 62 ml (p=0.014) compared with controls.
Maternal smoking is associated with reduced fetal measurements in the second and third trimesters but not in the first trimester. Mothers who do not quit smoking during the first trimester deliver smaller infants who go on to have adverse respiratory outcomes in childhood.
孕妇吸烟与胎儿出生体重降低和儿童期肺功能下降有关。本研究旨在确定孕妇吸烟何时首次影响胎儿生长，以及这与儿童期呼吸结局的关系。
本研究纳入了 1924 名孕妇的纵向队列。记录了 11 周（头臀长，CRL）和 20 周妊娠（股骨长，FL 和双顶径，BPD）的胎儿超声测量值以及出生测量值。确定了儿童期呼吸症状和肺功能。
在 1924 名原始研究参与者中，有 903 名在孕早期、1544 名在孕中期和 1737 名在孕晚期进行了胎儿大小测定。有 593 名（31%）报告了首次怀孕时吸烟，且与 CRL 降低无关。吸烟量与 FL 呈负相关（与最高三分位相比，最低三分位的平均降低量为 0.91cm，p=0.033）。与未减少吸烟量的母亲（n=331）和减少吸烟量的母亲（n=56）所生婴儿相比，继续吸烟的母亲所生婴儿的出生体重和长度相似，但均低于孕早期戒烟的 186 名婴儿（p≤0.020）。继续吸烟的母亲的孩子在 2 岁时喘息的发生率更高（OR 1.58，p=0.017），在 5 岁时因喘息就诊的次数更多（OR 2.18，p=0.030），用力呼气 1 秒量的平均值减少 62ml（p=0.014）。
孕妇吸烟与妊娠中晚期胎儿测量值降低有关，但与妊娠早期无关。孕早期不戒烟的母亲所生婴儿出生体重较小，日后儿童期呼吸结局不良。
