ual Desire is disappearing?

I am worried about mine and my husband's life. It seems like he is losing his ual desire and he's still in his 20's! He should just now be hitting prime! I am pregnant with our second child which is due next month so I'm hoping maybe that has something to do with it because it does seem like it has started getting less and less since I've got pregnant again. What's weird though is I was pregnant when we first got together and I was bigger than I am now and he still wanted a lot. I mean he's never been a nympho or anything but I can definitely tell his ual desire isn't as strong as it used to be. I've talked to him about it and he says he's still attracted to me but he says that he's tired of always having to be the one coming after me which he has been. I've never started and we've been together over 3 years. I'm afraid of being rejected. Also he is not happy with the way his body looks. He's gained quite a bit of weight since we've been together so he's not happy about that so I'm wondering if because he doesn't like his body if that might have something to do with it because he has mentioned that he doesn't feel like he's attractive to me when I don't go after him. He's still very loving in other ways. We still kiss, hug, snuggle and all that just the same. I'm just so sexually frustrated right now! Has anyone else had this problem? Take into consideration we have a toddler and my husband works full time so it's already hard to have a sex life as it is because our toddler is always awake and my husband is always tired from work!