141. Neighbourhood deprivation and foetal growth: The Generation R study

Introduction Embryonic development is affected by multiple parental lifestyle factors and environmental exposures. Neighbourhood deprivation is associated with lower birth weight and higher preterm birth rates. However, the effects of living in a deprived neighbourhood on embryonic and foetal growth have not been explored yet. Hypothesis We hypothesized that living in a deprived neighbourhood is negatively associated with embryonic and foetal growth. Therefore, our objective was to assess the association between neighbourhood deprivation and embryonic and foetal growth parameters. Methods We evaluated the association between living in a deprived neighbourhood and embryonic and foetal growth parameters in 1614 mothers with a reliable first day of last menstrual period and a regular menstrual cycle. Foetal measurements included crown rump length (CRL), head circumference (HC), femur length (FL), biparietal diameter (BPD), abdominal circumference (AC) and estimated foetal weight (EFW). Results A total of 1614 pregnant women were included. Most were of Western ethnicity (70.7%) and nulliparous (59.0%). Almost every pregnancy was spontaneously conceived (95.7%). The score for neighbourhood deprivation is determined for all 4-digit zip codes and takes income, education and employment into account. A low score represents a deprived neighbourhood. Using linear mixed models, we found a statistically significant association between the neighbourhood deprivation score and FL (adjusted β −1.06 [95% CI: −1.98, −0.15]) and EFW (adjusted β −0.96 [95% CI: −1.89, −0.04]), but not with CRL, HC, AC and BPD. Discussion This population-based study shows that residing in a deprived neighbourhood is statistically associated with some, but not all, foetal growth parameters. Possibly, foetal growth parameters have different degrees of receptivity to external factors such neighbourhood deprivation. The effects we found remained above and beyond individual SES, for which we adjusted. This suggests a separate neighbourhood level effect on embryonic and foetal growth.