Maternal smoking during pregnancy and behaviour problems in a birth cohort of 2-year-old Pacific children in New Zealand.

AIM: The present study investigated associations between maternal smoking during pregnancy and child behaviour problems in a cohort of Pacific Islands two-year-old children in New Zealand.

STUDY DESIGN: Data were gathered as part of the Pacific Islands Families (PIF) Study. Mothers of a cohort of 1398 Pacific infants born in South Auckland, New Zealand were interviewed when their children were six-weeks, 12 and 24 months of age. Within the context of a wider interview, data regarding cigarette smoking during pregnancy was obtained from 1038 biological mothers at the six-week interview and reports of child behaviour using the Child Behaviour Checklist were gathered when the children were 24 months old.

RESULTS: The prevalence rates of clinically relevant cases were higher in children of smokers compared to non-smokers for internalising (22.6% versus 15.2%), externalising (9.6% versus 5.7%) and total problem scores (20% versus 12.4%). Following adjustment for potential confounding factors, smoking was associated with a moderately increased prevalence of total behaviour problems (OR=1.75, 95% CI=(1.12, 2.74); p=0.015). For internalising scores, the effects of smoking appeared to be raised for children of non-partnered mothers (OR=3.35, 95% CI=(1.29, 8.67); p=0.013). For externalising scores, smoking appeared to have a greater detrimental effect on girls (OR=2.37, 95% CI=(1.12, 5.04); p=0.024).

CONCLUSIONS: Findings indicate there are significant effects of prenatal tobacco exposure on problem behaviour among young children. Smoking is a modifiable factor worthy of increased early preventive efforts.