Re: DO Nursing Tanks Affect Supply?
How old is your baby?
Most women's supply is lowest in the evening, so that's normal. My kids would cluster nurse like crazy in the evening when they were very little and I'd think there was no way they were getting anything since they'd been nursing for hours already, and then once in a while one of them would spit up enormous amounts and it was clear that there was plenty of milk. You don't have to have full-feeling breasts to have milk--they are the factories, not just storage spaces, so they are making milk at the very moment that it's being removed from the breast.
A lot of times babies just want to suckle and are actually frustrated that milk keeps coming out, so they pull off and fuss at the breast. My DD never took a pacifier, so she was much worse about that. Even my DS, who loves a pacifier, sometimes wants the breast, not the pacifier, and not the milk.
Is your nursing tank really tight? It would be more likely, IMO, that you'd be getting plugged ducts from a too-tight bra/tank than that it would be reducing your supply, absent other factors that would reduce supply (hormonal issues, not nursing baby enough).
Catherine, tandem nursing mama to Preschooler Girl 9/08 and Toddler Boy 3/11
Breastfeeding for 4 years and counting!