I top up. I have to. I really do have "poor supply".
During the first five days of my DD's life she lost 20% of her body weight as I was not producing enough milk: we had latching-on difficulties right from the start that were not picked up upon and my milk came and went, so to speak. I spent three weeks in tears because of what had happened. I expressed and expressed and expressed and eventually built up a supply of sorts but it will never, never be enough to exclusively breastfeed. This actually kills me, and it's taken me weeks and weeks to feel okay about giving her formula. I desparately wish things were different, but my DD became seriously ill because she hadn't, in effect, eaten for four days. We mixed feed now, I'm doing my best!
My only concern is that my DD is with us - my HV suggested she was gaining too much (she's 8.5 weeks) but turns out she's long, so the perfect weight.
So I'm afraid I've "fallen" for the advice of a number of health professionals, and now have a lovely, healthy DD, rather than the sick, grey one I had to watch them rehydrate via a drip at 5 days old. A breastfeeding midwife at the hospital made me feel terrible for giving her formula during this time, but had I not, it sickens me to think what might have happened. In the end, it was my community midwife, to continued to visit long after she had to, who convinced me that what I was doing was okay.
I don't mean to have a go at anyone, and I don't want to start a row, but sometimes topping up is the only answer. Believe me, I would give a limb to be able to breastfeed exclusively.
Sorry, bit of a rant there!