Page URL:

Genetic links to morning sickness

15 November 2010
Appeared in BioNews 584

A new study suggests that severe morning sickness may have a genetic component, because it is more likely to affect women whose mothers or sisters were also affected. Focusing on hyperemesis gravidardum (HG) - a type of morning sickness that causes severe vomiting and nausea in around one percent of pregnant women - the study found that women whose sisters had HG were 17 times more likely to develop HG themselves.

The researchers looked at 207 women with one or more sisters that had HG and compared them to a control group of 110 of the patients' female friends who had nausea-free pregnancies. They found that 14 percent of women who had HG also had an affected sister versus one percent of women who did not have HG. If other severe forms of morning sickness were taken into account then 34 percent of women with HG also had an affected sister compared with eight percent of controls. The study also found similar ratios when looking at mothers who had HG instead of sisters.

Dr Marlena Fezjo, a geneticist at the University of Southern California-Los Angeles and lead author of the study said: 'The degree of  heredity is very exciting because it suggests genes are involved, and when we find those genes we may finally understand the cause of severe nausea in pregnancy and be able to make new treatments that are designed to treat the cause rather than the symptoms'. However, Dr Andrej Grjibovski from the Norwegian Institute of Public Health, points out that women with HG might have been more likely to volunteer for the study if they had relatives with HG.

These findings backup earlier evidence that HG may have a heritable component, as suggested in an analysis of birth records, which found an increased risk of severe morning sickness in women whose mothers had the condition, and that identical twins are more likely to both develop the condition compared with non-identical twins.

HG is a significant problem that leads to the hospitalisation of more than 59,000 women a year in the US. Dr Fezjo and her team are now planning to compare the genes of women with and without HG, to identify those genes that may predispose women to the condition.

Familial aggregation of hyperemesis gravidarum
American Journal of Obstetrics and Gynaecology |  25 October 2010
Severe morning sickness runs in families
Reuters |  4 November 2010
12 April 2010 - by Dr Lux Fatimathas 
Scientists have uncovered a genetic link between low birth weight and developing type two diabetes in later life...
8 March 2010 - by Dr Vivienne Raper 
Babies with few teeth on their first birthday are more likely to need corrective dental surgery by age 30, a study has found. The UK and Finnish researchers also discovered ten genetic variants influencing tooth development during a baby's first year...
30 October 2000 - by BioNews 
Ten UK women are reported to be pregnant following treatment with the male impotence drug Viagra, prescribed by their consultant Dr Mohammed Taranissi. But fertility expert Lord Robert Winston has expressed concerns over what he called a 'reprehensible and dangerous' treatment. 'It is extraordinary that he has been allowed to...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.