Same here I was sick with my second from 4 weeks up until he was born. I threw up at least twice a day it got to the point I'd eat throw up feel better and continue to eat after that cause I knew I wasn't gonna get sick right away.
It happens sometimes when you have high levels of hormones with my first I vomited from 4 weeks over and over every day until the day I delivered.
Crazy hormones. A friend of mine was throwing up her entire pregnancy and even lost weight but the baby came out just fine. Most women get over the nausea after the first trimester but a few unlucky women do not. Have your wife eat food that has protein every three hours. Hot tea may help as well. Something soothing like chamomile.