I know some men get turned off b/c before they saw their partner as a "woman" and a lover... now they see her as a "mother" and it's hard to distinguish that just b/c she is a mother.. she is also a woman w/ needs.
I had the same question once before about breastfeeding. If you enjoy nipple stimulation during sex, etc... then when you have a baby....how do you completely change your mindset as to that the breast is just a baby feeder...and then once the baby is weened... how do you go back to feeling sexual about it?!??
It's kind of creepy in a way! lol