New findings on extreme nausea and vomiting in pregnancy

May 15 is Hyperemesis Gravidarum Awareness Day

Morning sickness- nausea and vomiting during pregnancy- occurs in up to 90 percent of women. Even animals, including a Gorilla named Calaya, have experienced it, too.

But about 2 percent of pregnant women suffer a more severe form known as hyperemesis gravidarum, or HG. The hallmark symptoms include rapid weight loss, malnutrition and dehydration due to unrelenting nausea and vomiting. It is the second-leading cause of hospitalization during pregnancy because some women will need intravenous fluids and, in the most severe cases, feeding tubes.

The HER Foundation, an organization dedicated to HG education, research and advocacy, offers information that compares the symptoms of normal morning sickness to HG.

Marlena Fejzo is an associate researcher at the David Geffen School of Medicine at UCLA who studies the condition. She suffered from HG herself and lost a pregnancy to it. She is encouraged by the advances being made to better understand this complex physiological disease.

"We finally have some answers as to the cause of this debilitating condition, debunking the theory that it is all in the woman's head," says Fejzo.

Here are 4 recent findings:

• HG is not caused by the suspected pregnancy hormones. It has long been assumed that human chorionic gonadotropin or estrogen, were the likely culprits of extreme nausea and vomiting. But recent research does not support this theory.
• It's in your genes. Instead, HG is likely caused, at least in part, by two genes known as GDF15 and IGFBP7 that are involved in the development of the placenta and play important roles in early pregnancy and appetite regulation. The proteins expressed by these genes are abnormally high in women with hyperemesis gravidarum.
• HG is biologically related to some symptoms in end-stage cancer. Those same two genes, GDF15 and IGFBP7, are coincidentally linked to cachexia, a debilitating chronic nausea and weight-loss syndrome that leads to death in about 20 percent of cancer patients.
• It's associated with neurodevelopmental delay in children. Women who experience HG are three times more likely to have children with developmental deficits, including attention disorders and language and speech delays. Researchers believe that nutritional deficiency early in pregnancy may be the cause rather than medications used to treat HG.

"My hope is that one day we can find a treatment," says Fejzo.