Arthur Edwards - Pool/Getty ImagesWith the happy news of Kate Middleton's pregnancy came a slightly more concerning revelation: the Duchess of Cambridge is being treated for Hyperemesis Gravidarum, a rare pregnancy complication.
The mom-to-be, 32, is under observation at Kensington Palace.
Prince William's wife was eight weeks pregnant with Prince George when she was hospitalized for the same condition 21 months ago. With Hyperemesis Gravidarum, vomiting becomes so excessive that pregnant women can become dehydrated and start to lose weight due to inadequate nutrition, Dr. Amos Grunebaum, director of obstetrics at New York Presbyterian/Weill Cornell Medical Center, told Today in December 2012. If not treated properly with intravenous fluids and anti-nausea medicine, Hyperemesis Gravidarum can be life-threatening to pregnant women and their fetuses, Dr. Grunebaum explained.
The condition is related to the pregnancy hormone human chorionic gonadotropin, or HCG, which increases in early pregnancy. Hyperemesis Gravidarum usually peaks in severity around week 12.
Grunebaum said about half of 1 percent of pregnant American women suffer from the condition. The American Journal of Perinatology, meanwhile, said it affects roughly two percent of pregnant women.
Hyperemesis Gravidarum might also indicate a healthy pregnancy. "It's a sign that the placenta is making more hormones," Dr. Peter Bernstein, a maternal-fetal medicine specialist at Montefiore Medical Center in New York City, explained. "The mother may be miserable but [she's] less likely to have a miscarriage."
As she's being treated, Middleton was forced to cancel her planned engagement in Oxford Monday.
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