or parents living in poverty, “diaper math” is a familiar and distressingly pressing daily calculation. Babies in the U.S. go through six to 10 disposable diapers a day, at an average cost of $70 to $80 a month. Name-brand diapers with high-end absorption sell for as much as a half a dollar each, and can result in upwards of $120 a month in expenses.  One in every three American families cannot afford enough diapers to keep their infants and toddlers clean, dry and healthy, according to the National Diaper Bank Network.