The impact of maternal smoking during pregnancy on depressive and anxiety behaviors in children: the Norwegian Mother and Child Cohort Study

Table 3 Associations between timing of maternal smoking and internalizing behaviors in children at 18 months, 36 months, and 5 years

	Dependent variable
	Internalizing behaviors (18 months; n = 62,119)	Internalizing behaviors (36 months; n = 50,223)	Internalizing behaviors (5 years; n = 19,155)
Maternal non-smokers	Reference	Reference	Reference
Maternal smoking in early pregnancy only	B = 0.20 (SE, 0.04), P <0.001	B = 0.17 (SE, 0.04), P <0.001	B = 0.15 (SE, 0.07), P = 0.03
Maternal smoking in late pregnancy	B = 0.11 (SE, 0.05), P = 0.04	B = 0.10 (SE, 0.06), P = 0.09	B = 0.21 (SE, 0.11), P = 0.06
Maternal smoking throughout pregnancy	B = 0.19 (SE, 0.02), P <0.001	B = 0.19 (SE, 0.02), P <0.001	B = 0.11 (SE, 0.04), P <0.01

Maternal non-smokers are the reference group, i.e., each of the three smoking groups is compared to this group in the analyses. Internalizing behaviors have been log transformed and standardized. B coefficients should be interpreted as units of standard deviation difference between each smoking group and non-smokers in the log-transformed scale for internalizing behaviors.
SE, Standard error.

ISSN: 1741-7015