Bivariate Analysis and Odds Ratios Table 1. Bivariate Analyses of Low Birth Weight and Maternal Weight Gain During Pregnancy Covariates Low Birth Weight Normal Birth Weight n % n % Odds Total 5,722 100 60,173 100 Ratio Maternal Weight Gain during Pregnancy (in pounds 0-20 1,917 A 12,146 E 21-31 1,626 B 15,973 F 32-41 1,102 C 15,405 41+ 1,077 D 16,649