This might be something you need marriage counseling for. Which would be an excellent idea anyway, considering what you've been through as a couple. If he's really serious about reconciliation he won't say no to counseling.
Consider:
- how are you physically, postbirth? are you still about the same weight? Men are very visual and if you've put on weight that could affect how attracted he is.
- make an extra effort with your appearance overall: look, smell and taste extra nice so you're as irresistable as possible.
- and on men being visual, try getting some fresh new sexy lingerie outfits to wear under a red silk nightgown. Just wear it around all innocent like you're not actually expecting or caring whether he takes the bait. You're just wearing it because
you like to look and feel sexy and confident. Try not to hang too much on his reactions. Play a little cheeky hard to get if he goes for a grope. I am sure it must be very hard to be turned down all the time

But desperate or stressful vibes around the topic of sex will have the opposite effect you would want! Try to remain
playful (even when rejected) so there's no pressure on him.
- have you thought about pelvic floor/kegel exercises? I gave birth to my third baby in 3 years just 6 weeks ago. We've had fantastic sex since then and I almost always orgasm from penetration alone (at the same time as him! I feel very lucky). But I am self conscious about any loss of tone 'down there'. Note: doing pelvic/kegel exercises without any resistance (without anything in the vagina) makes it very hard to do it right, to feel the right muscles contracting. I found this out after trying a pelvic floor exerciser! My first exerciser was ok but I just ordered a Gyneflex which I can't wait for.
- maybe you could initiate the sexual contact with just surprising him with some oral, but only enough to get him really interested (he wouldn't stop you from doing that would he?) and then tell him he'll have to come get you and make love if he wants to 'finish'
It's hard to really give accurate advice without any idea on what your relationship is like. But the fact that the sex stopped when you started showing in pregnancy makes me think he needs individual counselling, as well as MC for you together. Especially if none of the above tricks make any difference.