Talk to him lovely. I had a simliar prob which became extreme in him disappearing for a few weeks.. but all was fine eventually. It all transpired he was just terrified all of a sudden about hte whole thing.
he was terrified that he would hurt me, and the baby. He was worried about if there was anything wrong with the baby, despite scans and knowing she was fine, in as much as you can ever know. and everytime he got close or looked at me, it just raised all these fears again and again.
w have neve been happier than we are now, and it is only now really ( DD is 9 months old nearly) that we cn freely talk about what happened. my preg shape and changing body, just made him think every time about how our lives were changing nd his bigest fear of all: that he would not be able to provide foe us in the way he wanted, both practically and emotionally and he managed to convince himself he was just not good enough for us!
The only way to really get to the bottom of it and maybe get some resolve, is to talk, very calmly, openly and be understanding to him.. his life is changing too, he's living with a very differnt 'you' at the moment.
Try to just listen, and somehow, find a wy, deep inside to not be overly emotional about it with him. He prob already feels guilty about it...men find emotions and emotional women hard to cope with at the best of times, even if it is the woman they love...
Tell him its OKAY... even if its not, but by telling him it is, he will feel more able to talk openly and honestly to you.. trust me, it works every time... then you very slowly gradually feed in very carefully and subtly that actually its not, and why its not but only when he is comfortably talking about it all... trust me on this one.. very tried and tested ) tell him its ok, but that you need to understand why, and maybe you can help him, or find a way together to work through what ever it is he is feeling.
no easy answers lovely, other than, its NOT uncommon, you are not alone, and talk is the best way to resolve it.
Dont forget, that whilst you are preg the focus is on you, from everyone. everyone wants to know how you are, how your preganacy is going... how you are feeling etc. the fellas tend to get a bit sidelined dont they? i'm not saying the focus shouldnt be on you, but, well, i hope you know what i mean!
good luck, nd hope it all works out lovely