Re: LC thinks it's thrush, OB thinks it's not...
Wow, I'm sorry you got the misinformed brush-off from your ob! FTR, breastfeeding can be a bit ouchy at first as mom and baby get adjusted, but it does NOT hurt so badly that a mom would choose childbirth over nursing. That is NOT a normal level of pain.
I would go in to see your child's pediatrician. Pediatricians are often more familiar with thrush than obstetricians, and sometimes they even know that both mom and baby must be treated simultaneously, even if one member of the nursing pair is asymptomatic. And thrush is a good bet- you had antibiotics for GBS, your symptoms match. (I wouldn't worry about the nursing bras- you surely washed them before using them, and yeast is a normal comment of your skin flora. Thrush is just an overgrowth of what is normally there, often due to antibiotic-induced die-off of the good bacteria that keeps the yeast in check.) There is another possibility here that would match both the skin symptoms and the pain, and that's a bacterial infection of the skin. A dermatologist might be a good person to see in order to explore that possibility.
Pain after feedings, particularly if it's concentrated in the nipple, can be caused by vasospasms. Do you ever see the nipple appearing compressed, or changing color after feedings? It might blanch (turn white) or maybe turn bluish-purple before returning to a normal color.
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