Nonexclusive breastfeeding duration was greater at 3 months postpartum for all women in the treatment group ( adjusted relative risk : 1.22 ; 95 % confidence interval [ CI ] : 1.10-1 .34 ) but greater at 6 months for Spanish-speaking clients only ( adjusted relative risk : 1.29 ; 95 % CI : 1.10-1 .51 ) .