Time at Home for Whom? Unequal Returns of Paid Family Leave for Infant White Matter and Language Development

Paid family leave (PFL) may give parents more time with infants, ease financial strain, and support stable routines. Although PFL has been linked to child development, little is known about neural pathways that might underpin its benefits or whether associations vary across families. Using data from 274 infants in the HEALthy Brain and Child Development Study, we examined associations of maternal and paternal PFL with language ability at 12 months and white matter microstructure at 6 months. We tested whether associations varied by the corresponding parent's education. Neither maternal nor paternal PFL was directly associated with language scores or fractional anisotropy in the left arcuate, inferior longitudinal, or uncinate fasciculus. Maternal education moderated associations between maternal PFL and fractional anisotropy in the arcuate (p = .014) and inferior longitudinal fasciculus (p = .003; n = 148). In both tracts, PFL was associated with higher fractional anisotropy only among infants whose mothers had relatively high education. No comparable pattern emerged for language, the uncinate fasciculus, or paternal PFL. Findings suggest that the neurodevelopmental correlates of PFL may depend on family resources rather than operate uniformly across families, underscoring the need to pair paid leave with additional supports and resources.