I dunno, my ex was ok with the kids, and I was able to sleep & nurse at the same time (small boobs) but breastfeeding knocked my libido down to less than zero. Usually I run pretty hot, but while nursing it was like I couldn't care at all about sex, it felt like a chore, and when we did, I had both fear (because childbirth) and had to work just to get to a baseline level of desire at all. I always figured it was a natural birth control thing, nature helping so kids don't come too close together.