Intimate Partner Relationship Strain and General Health for Prospective Mothers and Their Child: A Target Trial Emulation Study

Objective: This study aimed to examine the causal effect of: (a) women’s exposure to intimate partner relationship strain during early young adulthood (ages 19–20) on self-rated general health at ages 23–28 and during pregnancy (32 weeks’ gestation) and (b) women’s exposure to relationship strain during early young adulthood and pregnancy on caregiver-reported 12-month-old offspring general health. To strengthen our causal inferences using observational data, we applied a target trial emulation framework. Method: This study makes use of maternal and caregiver-reported self-report data spanning young adulthood (threewaves) and the early perinatal period (two waves) obtained from a population-based subsample of mothers (N= 300) and their offspring (N = 521), participating in the Australian Temperament Project Generation 3. We estimated the effect (standardized mean difference [β]) using a G-computation procedure. Results: We observed no evidence for an association between maternal relationship strain in early young adulthood and maternal and offspring health (β=−.14 to.00). However, exposure to elevated relationship strain in pregnancy reduced offspring’s general health (β=−.29). Associations were strongest for patterns of persistent or time-limited elevated strain during pregnancy (β=−.34 and −.43, respectively), albeit with weaker evidence. Conclusion: Evidence for a causal effect of maternal exposure to relationship strain on lower offspring health was found. The results suggest that pregnancy may be a sensitive period for this intergenerational transmission. While the target trial emulation framework does not eliminate all possible biases, it strengthens causal inference and provides precedence for future research to further investigate these intergenerational transmission processes.