BMC Public Health 2009, 9:237 http://www.biomedcentral.com/1471-2458/9/237 Table 2: Distribution of adverse birth outcomes according to area characteristics, maternal birth place and education, singleton births, Québec, Canada, 1999–2003 PTB Foreign-born % PTB N Canadian-born % PTB N High school diploma or less % PTB N Some postsecondary or more % PTB N SGA birth % SGA N Area income Poorest Intermediate Wealthiest Trend p-value Immigrant density Low Intermediate High Trend p-value Income inequality High Intermediate Low Trend p-value Area income Poorest Intermediate Wealthiest Trend p-value Immigrant density Low Intermediate High Trend p-value Income inequality High Intermediate Low Trend p-value 6.4 6.3 6.0 0.07 4.9 5.6 6.4 0.0002 6.3 6.0 6.3 0.28 10.0 9.4 9.1 0.0009 9.0 8.7 9.7 0.006 9.4 9.3 10.7 0.008 21 657 22 312 15 505 2 043 7 579 49 852 35 819 16 783 6 872 21 639 22 301 15 492 2 042 7 573 49 817 35 801 16 763 6 868 6.7 6.4 5.9 <.0001 6.6 6.2 6.0 <.0001 6.0 6.3 6.6 <.0001 % SGA 8.8 8.2 7.3 <.0001 8.1 7.9 8.2 0.33 7.6 8.1 8.4 <.0001 91 628 96 177 103 344 112 714 111 006 67 429 80 636 100 812 109 701 N 91 542 96 102 103 278 112 628 110 924 67 370 80 560 100 746 109 616 PTB = preterm birth; SGA = small-for-gestational-age Among native-born mothers, SGA birth was more strongly associated with area poverty (OR 1.13, 95% CI 1.06–1.20) than immigrant density (OR 0.94, 95% CI 0.88–1.01) or income inequality (OR 0.95, 95% CI 0.88– 1.02) in the fully adjusted model (Table 4). Among for- eign-born mothers, area variables were not associated with SGA birth. Regression models stratified by maternal education Among mothers with some postsecondary education or more, areas with low relative to high immigrant density were associated with unfavourable odds of PTB (OR 1.15, 95% CI 1.06–1.25) in the fully adjusted model (Table 5). An association was not present among mothers with a high school diploma or less (OR 1.01, 95% CI 0.90– 1.12). Area poverty and income inequality were not asso- ciated with PTB for either social marker in the fully adjusted model. 8.1 7.9 7.4 0.004 8.1 7.7 7.6 0.01 7.3 8.0 8.0 0.004 % SGA 11.5 11.0 10.5 0.0002 10.8 11.3 11.1 0.20 10.7 11.1 11.3 0.03 31 393 25 718 19 920 27 536 22 350 27 145 22 161 25 257 29 613 N 31 365 25 703 19 910 27 514 22 335 27 129 22 149 25 241 29 588 5.9 5.7 5.4 <.0001 6.0 5.5 5.4 <.0001 5.5 5.6 5.9 0.002 % SGA 7.9 7.5 6.8 <.0001 7.2 7.0 8.0 <.0001 7.3 7.4 7.4 0.22 75 344 84 234 90 854 82 546 86 045 81 841 86 780 84 382 79 270 N 75 291 84 175 90 795 82 492 85 983 81 786 86 716 84 326 79 219 A different pattern was present for SGA birth. Among mothers with some postsecondary education or more, high relative to low area poverty was associated with unfa- vourable odds of SGA birth (OR 1.07, 95% CI 1.00–1.13), and high relative to low income inequality was associated with lower odds of SGA birth (OR 0.93, 95% CI 0.87– 1.00) in the fully adjusted model (Table 5). Among moth- ers with a high school diploma or less, area poverty was more strongly associated with SGA birth (OR 1.13, 95% CI 1.02–1.24); high income inequality was still protective, albeit not statistically significant (OR 0.92, 95% CI 0.83– 1.03). Unlike PTB, immigrant density was not associated with SGA birth among mothers with some postsecondary education or more. However, among mothers with a high school diploma or less, low relative to high immigrant density was protective for SGA birth (OR 0.90, 95% CI 0.81–0.99) in the fully adjusted model. Page 5 of 11 (page number not for citation purposes)