The primary outcome measured was exclusive breastfeeding when the infant reached 3 months of age, or 3 months corrected, if the infant was born prematurely. Exclusive breastfeeding was defined as no milk intake other than breast milk. Secondary outcomes included partial breast- feeding at 3 and 6 months, exclusive breastfeeding at six months, number of re-hospitalizations and physician visits in the first 6 months of life, and amount and type of lactation support given by child’s primary physician in first 6 months of life. We also a priori planned to compare exclusive breastfeeding proportions in our control group with those described in the Ottawa population