Maternal smoking cessation in early pregnancy and offspring weight status at four years of age. A prospective birth cohort study.
BACKGROUND
Maternal smoking during pregnancy is associated with fetal growth restriction, but also with increased risk for overweight in childhood. If the mother stops smoking in early pregnancy fetal growth is not restricted, but whether the risk for later overweight persists is unclear.


OBJECTIVE
To study if four year old children of mothers who stopped smoking in early pregnancy have higher mean body mass index (BMI) and/or increased odds of being overweight compared with children of non-smokers.


METHODS
Prospective population based study on Norwegian mothers and children.


METHODS
Among 711 children available for analysis, 540 were children of never smoking mothers, 114 of mothers who stopped smoking in early pregnancy, and 57 of mothers who continued to smoke throughout pregnancy.


METHODS
BMI and overweight defined by international criteria at age four.


RESULTS
Compared with children of never smoking mothers, children of smoking mothers had higher mean BMI (mean difference: 0.47; 95% CI: 0.10, 0.84 kg/m(2)), whereas mean BMI was not higher among children of mothers who stopped smoking (mean difference: 0.02; 95% CI: -0.24, 0.28 kg/m(2). Similarly, children of smoking mothers had increased odds for overweight (adjusted OR: 2.83; 95% CI: 1.13, 7.10), whereas children of mothers who stopped smoking did not have increased odds (adjusted OR: 1.29; 95% CI: 0.62, 2.68) compared with children of never smoking mothers.


CONCLUSIONS
In this study, the association between smoking exposure and childhood overweight did not persist in children of mothers who stopped smoking early in pregnancy.
Fasting
Magnus Hølmo
MH
Department of Public Health and General Practice, The Norwegian University of Science and Technology, Medisinsk Teknisk Forskningssenter, Trondheim, Norway. magnus.fasting@gmail.com
Øien
Torbjørn
T
Storrø
Ola
O
Nilsen
Tom-Ivar Lund
TI
Johnsen
Roar
R
Vik
Torstein
T
D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D016540:Smoking Cessation; D011795:Surveys and Questionnaires