In 1996 to 1997 , 17 046 breastfeeding mother-infant pairs were enrolled from 31 Belarusian maternity hospitals and affiliated polyclinics ( 16 intervention versus 15 control sites ) ; 13 879 ( 81.4 % ) children were followed up at 11.5 years , with 13 616 ( 79.9 % ) who had fasted and did not have diabetes mellitus .