Nausea and vomiting during pregnancy affect more than 80% of women. They're told it's normal. It will pass. It's a small consolation when you feel flu-like symptoms morning, noon, or night for weeks on end. "Morning sickness" is typically a first trimester discomfort, only sometimes lasting into the second or third trimester.
The symptoms are caused primarily by pregnancy-related hormones which heighten a woman's sensory response, particularly to smell. A sluggish, digestive system only adds to the problem.
Being aware of what triggers that wave of nausea will help you cope with the responses.