TABLE 3

Univariate Associations of Potential Confounders With Infant Feeding, Weight Gain, and BMI in the First Year of Life

NInfant Feeding ExposuresAnthropometric Outcomes
Formula Feeding in HospitalExpressed Milk Feedinga at 3 MoSolid Foods Introduced Before 4 MoExclusive Breastfeeding at 6 MoAny Breastfeeding at 12 MoWt Gain Velocityb 0–12 MoBMI z Score at 12 Mo
%%%%%Mean ± SDMean ± SD
Overall287025.056.917.118.146.6−0.11 ± 1.060.21 ± 1.07
Site
 Edmonton67032.2***49.5**17.7***15.1***38.3***−0.04 ± 1.12**0.36 ± 1.12***
 Toronto69215.263.021.416.142.9−0.05 ± 1.000.37 ± 1.01
 Vancouver62810.557.36.325.664.1−0.10 ± 1.070.11 ± 1.04
 Winnipeg88032.756.620.816.442.8−0.21 ± 1.040.06 ± 1.07
Maternal age, y
 <3086128.5*60.4**25.3***12.6***35.4***−0.08 ± 1.110.20 ± 1.11
 30–35122325.958.315.918.949.7−0.11 ± 1.030.19 ± 1.06
 ≥3578619.251.510.022.853.8−0.13 ± 1.050.24 ± 1.04
Prepregnancy BMI
 <25165620.6***56.115.1**19.5**52.1***−0.11 ± 1.030.12 ± 1.07***
 ≥25–3054624.857.217.518.546.4−0.12 ± 1.110.26 ± 1.04
 ≥3037739.759.824.312.629.4−0.10 ± 1.130.48 ± 1.04
Diabetes in pregnancy
 No271424.1***57.116.918.446.9−0.11 ± 1.060.21 ± 1.08
 Yes12641.254.719.712.139.8−0.15 ± 1.150.24 ± 0.98
Maternal ethnicity
 Asian41429.3***53.712.9**19.053.7*−0.10 ± 1.050.01 ± 1.02**
 White209322.558.117.118.645.6−0.13 ± 1.050.22 ± 1.06
 FN11740.452.825.215.041.80.04 ± 1.000.48 ± 1.06
 Other20130.953.921.612.947.90.05 ± 1.180.28 ± 1.23
Maternal education
 High school or less24238.7***41.9**33.5***9.0***26.4***−0.14 ± 1.130.27 ± 1.13
 Some postsecondary40928.856.920.114.739.6−0.04 ± 1.040.31 ± 1.06
 Postsecondary156223.059.015.318.748.1−0.13 ± 1.060.19 ± 1.07
 Postgraduate54318.356.912.923.458.5−0.11 ± 1.040.13 ± 1.03
Marital status
 Married262423.5***56.916.5**18.7**47.5**−0.12 ± 1.06**0.20 ± 1.06
 Single16140.458.827.29.135.00.11 ± 1.070.27 ± 1.20
Diet quality (HEI score)
 <7085528.7**57.123.9***13.2***36.2***−0.09 ± 1.090.24 ± 1.03
 70–7560523.653.815.518.644.8−0.11 ± 1.050.21 ± 1.09
 >75116822.058.614.421.255.0−0.13 ± 1.040.18 ± 1.06
Parity
 0155128.6***67.5***18.216.646.30.04 ± 1.04***0.23 ± 1.06
 196121.847.215.220.047.3−0.28 ± 1.050.15 ± 1.08
 ≥235719.038.016.719.346.1−0.32 ± 1.070.26 ± 1.09
Maternal smoking
 No255223.5***57.015.8***19.3***49.0***−0.14 ± 1.05***0.19 ± 1.07**
 Yes23635.557.931.76.022.60.22 ± 1.100.43 ± 1.04
Infant sex
 Female137825.055.814.7**19.8*47.2−0.14 ± 1.040.18 ± 1.03
 Male149225.057.919.216.546.0−0.08 ± 1.080.23 ± 1.11
Birth mode
 CS, elective30234.8***57.918.013.337.5**0.04 ± 1.070.37 ± 1.07**
 CS, emergency39843.360.116.717.045.3−0.13 ± 1.020.31 ± 1.03
 Vaginal216720.756.117.019.048.1−0.12 ± 1.060.17 ± 1.07
Infant gestational age, wk
 3855730.6**58.6*19.115.938.9**0.27 ± 1.02***0.29 ± 1.06
 39–40181322.854.815.818.647.7−0.14 ± 1.040.18 ± 1.06
 4150026.962.619.318.851.0−0.42 ± 1.030.20 ± 1.12
Infant birth wt, g
 <300033032.6**58.317.319.946.70.72 ± 1.00***−0.14 ± 1.06***
 3000 to <3500113723.057.216.118.345.80.15 ± 0.910.06 ± 1.02
 3500 to <400099123.256.917.318.048.1−0.32 ± 0.940.35 ± 1.06
 ≥400039329.654.918.816.144.0−0.97 ± 1.050.57 ± 1.10
  • N = 2870 infants from the CHILD cohort born ≥38 + 0 wk gestation. BF, breastfeeding; CS, cesarean delivery; FN, First Nations; HEI, healthy eating index.

  • a Of those reporting any breast milk feeding at 3 mo.

  • b Change in WFA z score from birth to 12 mo. Comparisons by χ2 test, ANOVA, or t test.

  • *** P < .001;

  • ** P < .01;

  • * P < .05.