Does Warm Parenting Mitigate Birth Risk Effects on Conduct Problems? An MZ Twin Differences Study

Can an emotionally warm and supportive post-natal environment mitigate the effects of low birth weight (BW) and premature birth on conduct problems (CP) in childhood (Aarnoudse et al., 2009)? There is evidence from... [ view full abstract ]

Can an emotionally warm and supportive post-natal environment mitigate the effects of low birth weight (BW) and premature birth on conduct problems (CP) in childhood (Aarnoudse et al., 2009)? There is evidence from correlational studies and at least one intervention that the answer is ‘yes’, via enrichment of psychosocial and learning experiences that support optimal development (e.g., Bagner et al., 2010). However, the prior work has not controlled for genetic factors, even though it is known that BW is heritable (Lunde et al., 2007) and parenting reflects, in part, child evocative gene-environment effects (Wang et al., 2017). To address this gap, we used an identical twin differences design and hypothesized that: 1) the combination of low birth weight (relative to co-twin) and short gestation would most strongly predict CP (relative to co-twin); and 2) this effect would be strongest when parental warmth was lowest, and weakest at the highest levels of parental warmth. The sample included 114 MZ twin pairs, assessed three times (5-7yrs; composite scores analyzed) for parent-rated CP and observer-rated parental warmth. The full regression model predicting MZ difference in CP was significant, F (7, 107) = 3.258, p = .004, R² = .18. The hypothesized two-way (β = .23) and three-way (β = -.33) interactions were significant. Post-hoc probing revealed that the anticipated BW-by-gestation interaction effect was weakest at high warmth, and strongest at low warmth. It was among the lower warmth households that we found the combination of low BW and earlier birth to most strongly predict higher CP (relative to co-twin). The findings indicate that future research should examine the interaction of BW and gestation length when predicting outcomes. More importantly, the results lend further credence to the emerging literature suggesting that enriched post-natal parenting environments can mitigate deleterious effects of birth risks on behavioral adjustment outcomes.

References

Aarnoudse-Moens, C., et al. (2009). Meta-analysis of neurobehavioral outcomes in very preterm and/or very low birth weight children. Pediatrics, 124(2), 717-728.

Bagner, D. M., et al. (2010). Parenting intervention for externalizing behavior problems in children born premature: An initial examination. Journal of Developmental and Behavioral Pediatrics, 31(3), 209-216.

Lunde, A., et al. (2007). Genetic and environmental influences on birth weight, birth length, head circumference, and gestational age by use of population-based parent-offspring data. American Journal of Epidemiology, 165(7), 734-741.

Wang, F. L., et al. (2017). Roles of response inhibition and gene–environment interplay in pathways to adolescents' externalizing problems. Journal of Research on Adolescence, 27(2), 258-277.