PITTSBURGH (KDKA) — From the moment Prince William and Kate Middleton’s “I Do’s” became history, Brits began speculating on when they might be seeing the appearance of the traditional “Heir and a Spare.”

That’s the way it is with royals.

But the lovely Duchess of Cambridge, lately spotted nibbling ginger cookies, an old and safe remedy for morning sickness is having a tough time of it.

Kate is experiencing acute morning sickness, known as Hyperemesis Gravidarum, which literally means “hyper-vomiting pregnant woman.”

“The woman with severe hyperemesis gravidarum can be very sick. They are miserable,” says Dr. Steven Caritis, who specializes in Maternal Fetal Medicine and pregnancy complications at Magee-Womens Hospital.

In rare cases – vomiting 20 to 30 times a day. The condition, which occurs in about one in 50 pregnancies, can cause serious dehydration, low blood pressure, weight loss, headaches and lethargy.

“My guess is what Kate is getting right now is intravenous medication, primarily fluids to expand her blood volume,” said Dr. Caritis.

The IV would also contain anti-nausea medications.

While the condition can last throughout the entire pregnancy, it’s not common.

“Most cases resolve by the end of the first trimester, or certainly by the end of the 20th week,” Dr. Caritis said.

Because morning sickness has a wide spectrum, more dangerous problems with similar symptoms have to be ruled out.

“From very mild nausea and vomiting to a very severe disease that involves the pancreas,” says Dr. Caritis.

It’s still not clear what causes morning sickness; available therapies aren’t a sure cure, but you can get relief.

“I think women need to be reassured that in most cases, with hydration and medical treatment, the baby will be fine,” Dr. Caritis added.

There is help in the pipeline.

Medicated patches are being applied to the skin for women who can’t keep anything down, and there are new and potentially beneficial treatments being studied, some of them at Magee-Womens Hospital.

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