Extreme morning sickness may cause neurodevelopmental disabilities in children, according to a newly-published study.



The joint UCLA-USC research finds mothers who suffer extreme morning sickness, known as Hyperemesis Gravidarum (HG), are three times more likely to give birth to children with neurological developmental issues than those who did not.

This type of morning sickness, defined by persistent, often-debilitating nausea and vomiting that typically lasts beyond the first trimester, also causes dehydration and weight loss. Its cause is unknown.



The researchers studied 312 children born to mothers with the condition and 169 children born to moms who did not have HG. The children whose mothers had severe morning sickness were more likely to be diagnosed with attention deficit disorder, speech delays and other issues than the children whose mothers did not suffer from HG, the study finds.



The study notes that the cause for the apparent link between HG and neurological developmental problems "is unknown, but may be due to maternal stress, abnormal hormone levels during fetal development and/or maternal-newborn bonding after birth, or malnutrition and vitamin deficiency." The authors say more research on this subject is needed.

"An encouraging finding is that we did not find any association with medications to treat [HG] and neurodevelopmental delays," says lead author Marlena Fejzo, an associate researcher in the David Geffen School of Medicine at UCLA. "So I speculate that the neurodevelopmental outcomes are more likely caused by nutrient deficiency early in pregnancy rather than medication.”



The study appears in the online edition of the European Journal of Obstetrics and Gynecology and Reproductive Biology.