Is it okay to ask my bf about his past hookups?

My boyfriend and I will have been together for almost a year in May. He’s my first boyfriend/romantic relationship but he’s dated and slept with other girls before me. We’re pretty close and he’s always been honest and sincere throughout our relationship.

Recently, I’ve been having the urge to ask him about his past dating/sexual experiences because it’s the one part of him he (understandably) hasn’t shared much of. I’m just not sure if I’d be overstepping the line by asking.

I don’t want to upset him or make him uncomfortable, but I can’t help but want to know. He knows pretty much all of my past experiences, since I experienced most of my “firsts” with him.

Hoping some of you ladies could help a girl out with some advice. Is it helpful to share your past relationships with a significant other? Or am I just looking to hurt myself?