Maternal smoking in pregnancy, fetal development, and childhood asthma.
OBJECTIVE
We examined the relationships among maternal smoking in pregnancy, fetal development, and the risk of asthma in childhood.


METHODS
We conducted a population-based cohort study, where all 58 841 singleton births were followed for 7 years using nationwide registries.


RESULTS
Maternal smoking increased the risk of asthma (adjusted odds ratio = 1.35; 95% confidence interval = 1.13, 1.62 for high exposure). Low birthweight and preterm delivery increased the risk of asthma at the age of 7, whereas being small for gestational age did not.


CONCLUSIONS
Maternal smoking in pregnancy increases the risk of asthma during the first 7 years of life, and only a small fraction of the effect seems to be mediated through fetal growth.
Jaakkola
Jouni J K
JJ
Institute of Occupational Health, The University of Birmingham, Birmingham, United Kingdom. j.jaakkola@bham.ac.uk
Gissler
Mika
M
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000453:epidemiology* / Q000209:etiology; D001724:Birth Weight / Q000187:drug effects; D015984:Causality; D002648:Child; D002675:Child, Preschool; D005260:Female; D005317:Fetal Growth Retardation / Q000139:chemically induced; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D008423:Maternal Age; D008431:Maternal-Fetal Exchange; D016017:Odds Ratio; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012137:Respiratory System / Q000187:drug effects; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology