It can be frustrating when your tried-and-true lovemaking positions (like the old standby, missionary) don't work, but there are plenty more, like:
REAR-ENTRY We don't love the term "doggie-style," but you know what we're talking about. You can also stand slightly bent over with one knee on a chair and your guy behind you.
SPOONING Lying in bed with your guy behind you can be intimate, and you don't need to use a lot of strength.
SEATED Have your guy sit in a chair. Sit on his lap, either facing away from him or sideways so you can have eye contact without your belly in the way.