My wife is pregnant with our first child. Last night she was up for well over an hour vomiting and feeling just awful. There are some rare complications of pregnancy which may cause severe nausea and vomiting. Despite the fact that intermittent vomiting is a problem for the mother, most babies do well if she can hold down fluids and easily digestible foods. During her prenatal visit, she should be checked for ketones in the urine.
Ketones are fat-metabolism byproducts, which can be toxic to developing babies.
Some women must be hospitalized for a few days for IV fluid administration to get their electrolytes back to normal. Folate deficiency has been implicated in extreme nausea. Be sure she is getting one milligram of folic acid per day. If she is taking a prenatal vitamin supplement, it has folic acid in it but could also be contributing to the nausea. Also, the iron in vitamin supplements could be a problem.