Dating a trans man

Amanda
Okay so today I went on a date with a trans guy and I really like him (I've known him for a while, this is just our first real date)! He's going to get too surgery soon and he has been on testosterone for 1 1/2 years. And I want to ask him about his situation but I really don't want to cross a line or ask something offensive because I don't want to ruin my chances with him. Can somebody give me some tips on how to go about this situation?