Study reveals women with morning sickness have healthier babies!

A new study found that women with symptoms of nausea and vomiting during pregnancy had fewer miscarriages and gave birth to bigger, healthier babies than women without symptoms. Morning sickness also was associated with fewer birth defects and better long-term development for the child, according to the study, a meta-analysis published in the August issue of Reproductive Toxicology.

As much as 85% of pregnant women develop morning sickness, which can range from mild to severe, the researchers said. Rapid increases in human gonadotropin, a hormone released by the placenta, are believed to help trigger the symptoms. Relatively high levels of the hormone, and possibly other hormones not yet identified, may contribute to a more favorable prenatal environment, the researchers said.

The analysis, conducted at the Hospital for Sick Children in Toronto, pooled data from 10 studies conducted in five countries from 1992 to 2012. The studies, which involved an estimated 850,000 pregnant women, examined associations between nausea and vomiting and miscarriage rates, prematurity, birth weight, congenital abnormalities such as cardiac defects and cleft palate, and long-term child development.

The risk of miscarriage was more than three times as high in women without symptoms of nausea and vomiting as in those with symptoms. Women 35 years old or older, who generally have a relatively high risk for miscarriage, benefited the most from the "protective effect" associated with morning-sickness symptoms, the study said.

Nausea and vomiting were associated with a reduced risk of low birth weight and short body length. Women with symptoms also had fewer preterm births: 6.4% compared with 9.5% for those without symptoms, one of the underlying studies found.

The risk of birth defects was reduced by between 30% and 80% in infants of mothers with symptoms. These children, when tested years later, also scored higher on tests of IQ, language and behavior.

Taking drugs to reduce symptoms of nausea and vomiting doesn't affect a woman's hormonal levels and therefore shouldn't alter any positive effects associated with morning sickness, said Gideon Koren, director of the Motherisk Program at Hospital for Sick Children and lead author on the report.

The report noted that only a few of the underlying studies examined in the meta-analysis included information about the severity of nausea and vomiting symptoms.