Just got a call from a working mom. Her baby is breastfeeding and gaining well even though she had to return to work at two weeks. She has been able to continue breastfeeding at night and pumping at work. At times, on weekends, she is able to store some bottles (actually platic bags of the Pl----x brand) to be used when she runs low. Once in each of the last two weeks, her sitter has had to use the frozen milk in addition to the milk mom has brought from the day before. Both times baby threw up about 20 - 30 minutes after the feed and appeared to throw up 'all' the milk she drank. She was fine, not fussy afterwards, breastfed when mom got there, and showed no ill effects. When it happened the first time, mom wasn't concerned. This second time she is asking is there something in the freezing that could make the milk intolerable for the baby. She's a very careful mom and says the milk has not been thawed an refrozen (in PR our lights go out often, but she says this has not been the case in her area as her clocks have not lost time). Milk is thawed quickly and given to the baby immediately. Any ideas out there? Jeanette Panchula, BSW, LLL, RN, IBCLC Puerto Rico