Li C Q, Windsor R A, Perkins L, Goldenberg R L, Lowe J B
Office of Educational Research and Development, School of Medicine, University of Alabama, Birmingham 35294-2041.
JAMA. 1993;269(12):1519-24.
To evaluate the impact of cotinine-confirmed smoking reduction during pregnancy on infant birth weight and gestational age at birth.
Group analyses from a prospective, randomized smoking-cessation intervention trial using cotinine levels to assess smoking cessation and reduction.
Four maternity clinics of Jefferson County Health Department in Birmingham, Ala.
A total of 803 pregnant smokers and 474 never smokers with a fetal gestational age of 32 weeks or less at the first prenatal visit to a clinic.
Infant birth weight and gestational age at birth.
Infants who were born to women who quit smoking (quitters) had the highest mean birth weight (3371 +/- 581 g), followed by infants who were born to women who did not change smoking behavior (no changers) (3043 +/- 587 g). The mean infant birth weight of infants born to the quitters, adjusted by mother's age, race, height, weight at baseline, and gestational age at delivery was 241 g heavier than that among the no changers (P = .0008) and 167 g heavier than the reducers (P = .04). The adjusted mean infant birth weight of infants born to the reducers was 92 g heavier than that among the no changers (P = .08). White reducers with baseline cotinine levels greater than 100 ng/mL had infants who were 241 g heavier than did white no changers. A 220-g difference was also seen in black reducers with a baseline cotinine level of 100 ng/mL or less. Although smoking cessation increased infant gestational age at delivery by 1 week, smoking reduction had little effect.
Cotinine-validated smoking reduction rates were positively associated with an increase in infant birth weight. While smoking cessation must continue to be the primary objective for pregnant smokers, specific intervention methods should also be directed toward smoking reduction for women who cannot quit.
评估孕期经可替宁确认的吸烟减少对婴儿出生体重及出生时孕周的影响。
一项前瞻性、随机戒烟干预试验的分组分析，使用可替宁水平评估戒烟和吸烟减少情况。
阿拉巴马州伯明翰市杰斐逊县卫生部门的四家产科诊所。
共有803名怀孕吸烟者和474名从不吸烟者，首次到诊所进行产前检查时胎儿孕周为32周或更小。
婴儿出生体重及出生时孕周。
戒烟女性所生婴儿的平均出生体重最高（3371±581克），其次是吸烟行为无变化的女性所生婴儿（3043±587克）。经母亲年龄、种族、身高、基线体重及分娩时孕周调整后，戒烟女性所生婴儿的平均出生体重比吸烟行为无变化的女性所生婴儿重241克（P = 0.0008），比吸烟减少的女性所生婴儿重167克（P = 0.04）。吸烟减少的女性所生婴儿经调整后的平均出生体重比吸烟行为无变化的女性所生婴儿重92克（P = 0.08）。基线可替宁水平大于100 ng/mL的白人吸烟减少者所生婴儿比白人吸烟行为无变化者所生婴儿重241克。基线可替宁水平为100 ng/mL或更低的黑人吸烟减少者所生婴儿也有220克的差异。虽然戒烟使分娩时婴儿孕周增加了1周，但吸烟减少的影响不大。
经可替宁验证的吸烟减少率与婴儿出生体重增加呈正相关。虽然戒烟仍应是怀孕吸烟者的首要目标，但对于无法戒烟的女性，也应针对吸烟减少采取特定的干预方法。
