Thousands of women in the UK may be being driven to terminate their pregnancies each year because of a condition that causes severe vomiting during gestation.
A survey of more than 5,000 women with hyperemesis gravidarum (HG), published today, is the largest study ever into the 'devastating' illness.
It found that 5 per cent of HG sufferers terminated a planned pregnancy because the symptoms become too overwhelming, while more than half considered it.
A quarter of affected women said they experienced suicidal thoughts, while 6.6 per cent regularly considered taking their own life.
Up to one in 30 pregnant women suffer from the HG each year in the UK and US. It causes persistent and excessive nausea and vomiting.
King's College London researchers, who conducted the survey, argued it was critical pregnant women can get rapid access to anti-sickness medication.
The Duchess of Cambridge suffered from the condition when expecting her first child Prince George in 2012 and was admitted to hospital for three days. She
The survey, published today in Obstetric Medicine, revealed 4.9 per cent of women said they terminated a wanted pregnancy because of HG, while 52.1 per cent considered it.
Previous studies have found as many as 15.2 per cent of women with the condition had an abortion.
Women were more likely to get an abortion if HG left them unable to look after their existing children, or felt it was the only way to stop suicidal thoughts, the researchers said.
They survey allowed women to write comments as well as responding to multiple choice questions.
One woman said she doesn't think she will 'ever get over it', but 'had no other option at the time.'
A study of more than 5,000 woman in the UK who suffered from hyperemesis gravidarum revealed five per cent have terminated a wanted pregnancy because their symptoms were so debilitating, while more than half considered it
Hyperemesis gravidarum (HG) is a condition that causes persistent and excessive vomiting during pregnancy.
Sufferers can be sick lots of times every day and be unable to keep food or water down, impacting their daily life.
It is unlikely to harm the baby, but if it causes a women to lose weight during pregnancy there is an increased risk their baby will have a low birth weight.
It is different to sickness during pregnancy — often called morning sickness — which is normal and affects eight in 10 pregnant women. For most, this stops or improves around weeks 16 to 20.
Meanwhile, HG may not get better by this point and can last until the baby is born.
Symptoms of HG include prolonged and severe nausea and vomiting, being dehydrated, weight loss and low blood pressure.
Being dehydrated raises the risk of having a blood clot — deep vein thrombosis — but this is rare.
It is not clear what causes the condition, or why some women get it and others don't.
Some experts think it may be linked to the changing hormones in the body that occurs during pregnancy.
And there is some evidence that it runs in families and women who suffered it during their first pregnancy are more likely to have in any subsequent pregnancies.
Women suffering from HG can be given medicine to improve their symptoms, such as anti-sickness drugs, vitamins B6 and B12 and steroids.
Some women have to be admitted to hospital if their nausea