I used to be a hard sleeper and to this day I cannot and do not hear the alarms go off!! Although I hear every little breath mine takes and he is 4.If he tosses or turns, whines or cries I hear him instantly. It will change for you when the baby is here. Don't worry
Thank you for the responses ladies it really helps put my mind at ease (:
I've read a study that said babies cries are almost always guaranteed to wake up a woman/mom simply because you are subconsciously listening for it. It's good that you are thinking about it, having that thought in your head makes you more likely to wake up.
I think moms just have an ear for their baby's cry. Each cry is unique and you will quickly learn to listen for it.
I'm a hard sleeper but when my babies cry I practically jump out of bed. I think things just change when you have kids. Oh and my oldest is almost five so I've had her for a while lol