Morning Sickness Passed Down

The daughters of women who suffered from a severe form of morning sickness are three times more likely to be plagued by it themselves, according to a recent report by Norwegian researchers.

This form of morning sickness, called hyperemesis gravidarum, is extreme nausea and vomiting that often leads to weight loss, fainting or lightheadedness, and dehydration. It occurs in nearly 2 percent of all pregnancies and might require hospitalization.

The new study suggests “a strong influence of maternal genes” on the development of the condition, said lead researcher Ase Vikanes, a graduate student at the Norwegian Institute of Public Health in Oslo.

For the study, researchers collected data on 2.3 million births from 1967 to 2006. They tracked the incidence of hyperemesis gravidarum in more than 500,000 mother-daughter pairs and almost 400,000 mother-son pairs.

They found that if a mother had the condition, her daughter was three times more likely to develop it as well. However, there is no increased risk to the female partners of men whose mothers suffered through it.

For more information about hyperemesis gravidarum, visit the American Pregnancy Association website at