Husband has had a rash after sex, I am pregnant and it has never happened before?

Did you use any lubricant? Sometimes the lubricant can cause a rash. Also, when you are pregnant, you are more prone to yeast infections. It's a little-known fact that men can also get yeast infections. It's possible that you may have had a high yeast content and he could have gotten a rash from it. The best way for him to take care of it is to let it get some air. Have him walk around in some cotton boxers when he's not at work. He can also try applying some non-flavored yogurt to the affected area in addition to letting it get air.