The compared the influence of the residential environment and maternal country of origin on birthweight and low birthweight of infants born to recent immigrants to urban Ontario.  They linked delivery records (1993-2000) to an immigration database (1993-1995) and small-area census data (1996).  The data were analyzed with cross-classified random-effects models and standard multilevel methods.  Higher-level predictors included four independent measures of neighborhood context constructed by factor analysis and maternal world regions of origin.

Births (N=22,189) were distributed across 1,396 census tracts and 155 countries of origin.  The associations between neighborhood indices and birthweight disappeared after we controlled for the maternal country of origin in a cross-classified multilevel model.  Significant associations between world regions and birthweight and low birthweight persisted after they controlled for neighborhood context and individual characteristics.

The residential environment has little, if any, influence on birthweight among recent immigrants to Ontario.  Country of origin appears to be a much more important factor in low birthweight among children of recent immigrants than current neighborhood.  Findings of neighborhood influences among recent immigrants should be interpreted with caution.