I breast fed for over 8 months, but Iwasn't especially low carbing. I was told, that to breast feed, that I had to keep my blood sugar sightly higher...ie aim for 8 rather than 7 etc.
Sorry, I don't really know, but if I were you, I would spend the first few weeks getting breast feeding establisehd and eating the best you can (it can be difficult to eat at all in those first few weeks...sooooooo, tired) etc.....and if you have a baby who likes breast feeding...then you can try lowering your carbs, and see what happens? If it is impacting baby, they will soon let you know, as you will find that they will want to be fed 24/7...so youwill know that it isn't working. They do say, that for all feeding mothers, need more calories when breast feeding, but I do not know if they say the same about carbs. I suspect if you ask, they will tell you not to low carb and breast feed, but as they also say that in general, I am not sure whether it is worth anything?