Social predictors of continued and indoor smoking among partners of non-smoking pregnant women: the TMM BirThree Cohort Study

Associations of Education and Income with Secondhand Smoke Exposure Among Non-smoking Pregnant Women in Japan: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

OBJECTIVES

There is accumulating evidence that lower socioeconomic groups are more exposed to secondhand smoke (SHS) than higher ones in the general population. The objective of the study was to examine the associations of education and income with SHS exposure among non-smoking pregnant women in Japan.

METHODS

We analyzed data from 11,615 non-smoking pregnant women in Japan who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study from 2013 to 2017. SHS exposure was defined as indoor exposure to someone else's cigarette smoke ≥ 1 day/week during pregnancy. Multiple logistic regression analyses were conducted to examine whether pregnant women's educational attainment or equivalent household income was associated with SHS exposure, adjusting for covariates. Stratified analyses by work status were also conducted.

RESULTS

The prevalence of SHS exposure during pregnancy was 32.6%; 27.6% among non-working women and 35.8% among working women. Lower educational attainment was associated with an increased risk of SHS exposure; the odds ratio of high school education or lower compared with university education or higher was 1.87 (95% confidence interval, 1.66-2.10). Lower equivalent household income was associated with an increased risk of SHS exposure; the odds ratio of the lowest compared with the highest level of income was 1.53 (95% confidence interval, 1.35-1.74). These associations did not differ between non-working women and working women.

CONCLUSIONS FOR PRACTICE

Associations of education and income with SHS exposure imply that educational interventions and financial incentives are needed for pregnant women and their household smokers.

Association of maternal psychological distress and the use of childcare facilities with children's behavioral problems: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

BACKGROUND

Childcare facilities are a factor that lowers the established association of mother's postnatal psychiatric symptoms with children's behavioral problems. However, no studies have considered the prenatal psychiatric symptoms yet. This study examined whether the use of childcare facilities moderates the association of maternal psychological distress in early pregnancy and at two years postpartum with behavioral problems in children aged four years.

METHODS

The present study was based on the data from 23,130 mother-child pairs participating in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. K6 was used to classify maternal psychological distress in early pregnancy and at two years postpartum into four categories: none in both prenatal and postnatal periods (none), only the prenatal period (prenatal only); only the postnatal period (postnatal only); both prenatal and postnatal periods (both). The children's behavioral problems were assessed using the Child Behavior Checklist for Ages 1½-5 (CBCL) aged four years. The clinical range of the externalizing, internalizing, and total problem scales of the CBCL was defined as having behavioral problems. To examine whether availing childcare facilities moderates the association between maternal psychological distress and children's behavioral problems, we conducted a stratified analysis based on the use of childcare facilities or not, at two years of age. The interaction term between maternal psychological distress and use of childcare facilities was included as a covariate in the multivariate logistic regression analysis to confirm the p-value for the interaction.

RESULTS

The prevalence of the clinical ranges of externalizing problems, internalizing problems, and clinical range of total problems were 13.7%, 15.4%, and 5.8%, respectively. The association of maternal psychological distress with a high risk of children's behavioral problems was significant; however, the association between prenatal only psychological distress and externalizing problems in the group that did not use childcare facilities was not significant. Interactions between the use of childcare facilities and maternal psychological distress on behavioral problems in children were not significant.

CONCLUSIONS

Use of childcare facilities did not moderate the association of maternal psychological distress in early pregnancy and at two years postpartum with behavioral problems in children aged four years.