Cesarean delivery was not associated with anemia at 6 mo in cohort 1 ( adjusted OR : 1.05 ; 95 % CI : 0.93 , 1.19 ) ; however , cesarean delivery was associated with increased anemia at 12 mo in cohort 1 ( adjusted OR : 1.19 ; 95 % CI : 1.04 , 1.37 ) and at 58 mo in cohort 2 ( adjusted OR : 1.11 ; 95 % CI : 1.08 , 1.15 ) .