It isn't common for a n/b to sleep that long and not affect the mother's milk supply and the baby's ability to thrive.

My n/b wasn't sleepy from any factors such as jaundice and she would sleep 5 hrs overnight, straight from hospital. We could tell she was thriving from the number of wet and dirty nappies she had (lots!) and the fact she was back at her birthweight within four days. But without a doubt, my baby was the exception to what most n/bs are like and need! 10 hrs seems really excessive. She'll probably find as she wakes baby more to feed that baby starts demanding more and becoming less settled. This is a good thing, since it means she's getting what she needs.