Higher child-raising costs due to maternal social isolation: Large population-based study in Japan.

BACKGROUND: To assess the association between maternal social isolation and the child-rearing costs among mothers with 6-month-old infants. METHODS: Data was analyzed from a population-based birth-cohort study in Japan, the Longitudinal Survey of Babies in the 21st Century (n = 40,643). Maternal isolation was defined by lack of social support among mothers expressing difficulties with child rearing. Child-rearing costs for one month (when the infant was 6-months-old) were self-reported in units of JPY 10,000 (approximately 80 USD). The association between maternal social isolation and child-rearing cost was assessed using generalized linear models adjusted for child, maternal, and family level characteristics. RESULTS: Of the sample, 258 (0.6%) women were classified as socially isolated. In the crude model, isolated mothers paid JPY 6980 (95% confidence interval [CI]: 4753-9207), approximately USD$87, more per month on child-rearing expenses compared to non-isolated mothers. This finding was similar in the multivariable adjusted model (marginal effect: JPY 4,186, 95% CI, 2235-6136). Stratified analysis comparing low income vs. non-low income mothers showed that, among the former group, socially isolated mothers spend more on child rearing than mothers who are not isolated (marginal effect: JPY 13,218, 95% CI:784 to 2565), while among the non-low income group, a significant association was not observed. CONCLUSIONS: Socially isolated mothers spent JPY4,186 (approximately USD 35) more per month on child-rearing costs compared to non-isolated mothers when the infant was aged 6 months old. In nationwide terms, this cost could be roughly calculated as JPY 350 million (approximately USD 2.9 million) in 2001. Provision of social network connections and support for socially isolated mothers is suggested to be an efficient public health policy.