Young motherhood and child outcomes

Abstract

There is considerable evidence that childbearing at a young age is associated with poorer outcomes for both mother and child. However, international research suggests that much of this association is not causal – children born to young mothers might still have had poor outcomes even if their mother had delayed their childbearing. Data from the Longitudinal Study of Australian Children (LSAC) shows that children aged 4-5 years whose mothers were under 25 when they were born have distinctly lower levels of functioning than those with older mothers. Census data on 16-18 year olds who are still living with their mother show that this disadvantage carries through to education and labour market outcomes. Those born when their mother was in her teens are much less likely to be still in school. We cannot, however, assume that all these differences are directly caused by being born to a young parent. It is quite possible that such associations could arise because of the different characteristics of the mothers (and fathers) who have their children when young. Testing for a causal relationship is important in formulating policy responses to these issues. If young motherhood causes negative outcomes for either the mother or child then this provides support for policies to discourage early childbearing. If, on the other hand, this association arises because of underlying socio-economic disadvantage that influences both young fertility and later outcomes, then such fertility interventions will have no impact on later outcomes. Evidence from other countries is mixed. A recent US survey concluded that being born to a teen mother does not have an impact upon the school test scores of offspring, but may have an effect on other behavioural outcomes. Recent UK research on the other hand, has found a significant negative impact on schooling and employment outcomes. This report uses several different methods to test for the existence of a causal impact of mother’s age at birth in Australia. Outcomes for young children and for teenagers/young adults are considered. Using the LSAC survey, it is found that children born to mothers aged 30 have about half a standard deviation higher learning outcome score than children born to mothers aged 18. For social-emotional outcomes the effect is larger, at 0.7 standard deviations. The report then controls for background socio-economic characteristics using two different approaches. The first approach holds constant a range of conventional socio-economic background variables. The second approach also holds constant the mother’s age at the birth of her first child. The results from the two approaches are similar. The association with learning outcomes disappears, but the relationship with social-emotional outcomes persists. However, given that the latter outcome score is entirely parent-rated, this result could possibly be due to the different expectations of parents of different ages. The Household Income and Labour Dynamics in Australia (HILDA) survey is then used to examine outcomes for teenagers and young adults. The HILDA data allows us to control for all fixed characteristics of families (even those unobserved) by comparing the outcomes of siblings. We find no significant difference in sibling year 12 completion (controlling for a first-born child effect). A similar story applies to youths’ self-ratings of their educational performance and life satisfaction. These conclusions rule out any large effects of mother’s birth age on these outcomes, but the sample size in HILDA is insufficient to rule out modest impacts of birth age. For example, we cannot reject the hypothesis that the impact on school completion of being born to an under 23 year-old mother is as large as the 13 percentage point difference for teenage mothers found in UK research. The results of this research cannot thus be described as conclusive. There is some evidence of an impact of mother’s age at birth on social/emotional outcomes of young children, but this could be due to parental expectations at different ages. For teenage outcomes, we cannot find any impact when comparing siblings, but larger samples are needed in order to rule out effects such as those found in some other studies in other countries.