I'm super moody and emotional since I'm 18 weeks pregnant so I would like some opinions on this.

My fiancé has no interest in sex since we've found out we're expecting. We haven't had sex since January. I tried getting things going last night and he blatantly told me no, rolled over and went to sleep.

How should I handle this? I know talking to him is the best answer but how should I bring it up? It's very hard for me to not just close up into myself and push him away. I just feel completely unwanted and unattractive to him.