What are the effects of cigarette exposure in pregnancy?

January 01, 0001

What are the effects of cigarette exposure in pregnancy?

These US researchers sought to estimate the effect of cigarette smoke exposure on asthma severity as well as obstetric and neonatal outcomes in pregnant women with asthma. They performed a secondary observational analysis of pregnant women with mild to moderate-severe asthma enrolled in a prospective observational cohort study and a randomized clinical trial (RCT). A baseline questionnaire detailing smoking history and passive household smoke exposure was given to each patient. Data on asthma severity and obstetric and neonatal outcomes were compared to the smoking data.

The researchers report: "A total of 2,210 women were enrolled: 1,812 in the observational study and 398 in the RCT. Four hundred and eight (18%) women reported current active smoking. Of the nonsmokers, 790 (36%) women reported passive household smoke exposure. Active smoking was associated with more total symptomatic days and nights of sleep disturbance. Among the newborns of active smokers, there was a greater risk of small for gestational age less than 10th percentile, and a lower mean birth weight. There were no differences in symptom exacerbation or outcome between nonsmokers with and without passive household cigarette smoke exposure."

The authors concluded: "Among pregnant women with asthma, active but not passive smoking is associated with increased asthma symptoms and fetal growth abnormalities."

This study finds active smoking worsens asthma and increases risk of small for gestational age infants, but, perhaps surprisingly, no such findings occurred with passive smoke exposure.

For the full abstract, click here.

Chest 137(3): 601-608, March 2010
© 2010 American College of Chest Physicians
The Effect of Active and Passive Household Cigarette Smoke Exposure on Pregnant Women With Asthma. Roger B. Newman, Valerija Momirova, Mitchell P. Dombrowski, et al. Correspondence to Roger B. Newman: [email protected]

Category: R. Respiratory, W. Pregnancy, Family Planning. Keywords: cigarette, pregnancy, asthma, fetal growth, passive smoke exposure, secondary observational analysis, journal watch.
Synopsis edited by Dr Paul Schaefer, Toledo, Ohio. Posted on Global Family Doctor 23 April 2010

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