Updated: Tuesday, 04 Dec 2012, 7:07 PM EST
Published : Tuesday, 04 Dec 2012, 7:07 PM EST
NEW HAVEN, Conn. (WTNH) -- The royal announcement that Prince William and his wife Kate are expecting is raising awareness of a little known condition.
The Duchess of Cambridge is one out of two hundred pregnant women coping with extremely severe morning sickness.
It's day 2 in the hospital for the Duchess of Cambridge, the former Kate Middleton, pregnant with a future heir to the British Throne. Less than 12 weeks into her pregnancy, she's battling what's called hyperemesis graviderum.
"For most patients, it means unable to stay hydrated," Dr. Joshua Copel said.
Dr. Copel at Yale School of Medicine specializes in high risk pregnancies. Severe nausea and vomiting are common symptoms and can lead to dehydration in the first trimester.
"Causes include a multiple birth and an overactive thyroid.
"Most of the time when it happens, it's one baby," Dr. Copel said.
"We will routinely as a first step if we think somebody has hyperemesis, we will be checking them with an ultrasound and to make sure there is only one and to be sure the placenta looks normal and often check thyroid function," Dr. Copel said.
Less than one percent of pregnant women require hospital treatment and are easily managed.
"She would be getting first intravenous fluids, just saline solution with some sugar, after a number of days we would consider transitioning over to intravenous feedings, which means a different type of intravenous lines being in place," Dr. Copel said.
Dr. Copel points out the baby is not in any danger at this early stage.
"Its pretty small, very tiny at this point in pregnancy. It does not need a lot of nutrition," Dr. Copel said.
Dr. Antonette Dulay is now 36 weeks pregnant but remembers her first trimester.
"I would wake up in the morning, really with that feeling of just being ill, just being tired and just nausea," Dr. Dulay said.
That miserable feeling passed going into her second trimester.
"I was actually at a point once when I was worried that I would need to be hospitalized for hydration and what not," Dr. Dulay said.
Like most women with mild to severe cases, the symptoms ease as the pregnancy progresses beyond the first 12 weeks.
An "Ask Yale Medicine" blog has been posted with a Q&A with Dr. Christian Pettker of Yale about the matter.