Family poverty, neighbourhood greenspace and perinatal outcomes.

Objective: The relationship between low income and adverse perinatal outcomes, such as low birth weight and developmental delays, is well established making the search for protective factors important. One such factor may be neighbourhood greenspace. This study elucidates the role of urban neighbourhood greenspace in the relationship between income and perinatal outcomes in a nationally representative birth cohort from the UK.

Methods: Data on 14 050 infants participating in the initial wave at age 9 months of the Millennium Cohort Study were used (51% male, 20% non-white, 52% living in disadvantaged areas). We tested whether the association between income and perinatal outcomes is moderated by urban greenspace (measured in deciles) before and after adjustments for confounding. The perinatal outcomes included birth weight, gestational age (in days), communication and motor delays. The models were adjusted for the infant's sex and ethnicity, mother's age, education, substance use and mental health as well as area disadvantage and air pollution.

Results: Neighbourhood greenspace moderated the association between income and gestational age, even after adjustment for all confounders, b=-0.11, 95% CI (-0.215, -0.004). For births in low-income households, in particular, it was associated with an increase in gestational age by an average of approximately 3 days. However, after adjustment, greenspace was not found to influence birth weight, communication or motor delays at age 9 months.

Conclusion: The biophilic design of urban environments is a modifiable factor for improving perinatal outcomes in the UK as urban greenspaces appear to be mitigating the risk of preterm birth associated with family poverty.