I had mastitis a few times with DD and found my maternity bra's seemed to start it off. I haven't had it since wearing normal bra's and have been wearing normal ones since DD was about 4-5months old (several sizes larger then I normally wear) DD is 21months and still feeding a few times in 24hours. I also noticed as a midwife that lots of women don't seem to wear maternity bra's. If I have another baby I think I'll just keep wearing non maternity bra's.