Why did the number of american women breastfeeding their babies drop dramaticly after wwii?

Overlapping issues: This era saw many changes in family life.Many women worked outside the home & needed an easier way to feed the child. Soon after the first antibiotics (wwii), we had staph outbreaks in nurseries with germs that weren't killed by penicillin.Many thought breast feeding spread the germs so babies were wrapped in sterile blankets & bottle fed. A home made formula was promoted & the rest is history.