Previous breastfeeding does not alter thymic size in infants dying of sudden infant death syndrome

The relationship between thymic weights and previous feeding histories was examined in 294 infants of 37 wk gestation or more dying of sudden infant d eath syndrome (SIDS). One hundred and sixty-five infants had been breastfed exclusively, 89 had been partially breastfed and 40 had never been breastf ed. We found no relationship between thymic weight and type of previous fee ding. The difference between these findings in SIDS and the substantially g reater thymic size previously reported in 4-mo-old breastfed living infants deserves further study.