Oh, my gosh. I have them all. Well, most of them. Mostly, I have an honest-to-goodness low milk supply. It has been hell figuring this out, and if I read in one more place that "it's rare, don't worry about it, it's definitely not that", I will SCREAM. I post a lot in the thread in the BF forum about low milk supply.
This has made it much more difficult to nurse, as she gets very upset and frustrated at not getting any milk. At thsi point, I'm on a maximum pumping schedule, taking domperidone (max dosage), increased thyroid medication, continuing low dosage metformin (I have PCOS and am hypothyroid.. no wonder I have low supply!), and now.. I'm on TWO WEEKS of diflucan for a milk duct yeast infection. Good lord, it hurts. Take this seriously, women, because if you get it in the ducts, you will be reminded of labor pain. I'm serious. I can't believe how much this hurts. I now realize I had the infection on the nipple of that breast for a long time (well, I'm at six weeks now about), but just thought it was poor latching. Um, nope. (we do have latching problems but those cause different pains!)
Anyway, so we have all the latching problems described by others here. I don't use a shield, but what I do now is try to be more relaxed about the whole thing. I don't force nursing, and we use bottles all the time (she gets about half formula now, even with everything I'm doing). She gets mostly pumped breast milk other than that, but at least once a day I strive to have an actual nursing event happen. This happens best when she is not very hungry, and I'm late for a pumping session and therefore as full as I"ll get. If she's very hungry it is a FREAKING DISASTER trying to nurse her. Relaxing and not trying to force it, for us, has really helped.
This is close to the opposite BF relationship I had hoped and dreamed of, between the pumping, the forumula, and all the medications I'm taking. We all just do our best. I wish I had known that low supply does happen, it's a real risk, and my medications during pregnancy could have been adjusted to help prevent this from happening. OH well. -j