no sex drive.

I'm 21 weeks pregnant and my SO and I used to make love at least every other day if not daily.. It's been three weeks now and I have zero desire. He has a very high sex drive and I feel bad because I'm so nauseated all the time I can't even give him head anymore without fear of actually vomiting, which means neither one of us enjoys it. Is it a pregnancy symptom to not have a sex drive? I really hope it doesn't last for the rest of the pregnancy! I miss sex  I miss enjoying being physically intimate with my man. Have any mamas experienced this and how long did it last? Did anything help?