Inadvertently, twice. My boys refused them, from a very young age. It made for very miserable first days back to work for me and especially daddy at home with them. They reverse cycled, got plenty of milk when I was home and took a cup early. I did come home for lunch most days.They were both healthy, big thriving babies. (And I feed them every two hours all night long, in addtion to working all day. Not ideal but it worked for us.)
loving my dh and our littles (dd ~ 11 yrs, ds ~ 9 yrs, ds ~ 7 yrs, dd ~ 5 yrs and baby brother ~ 20 mo)