Morning sickness linked with lower risk of miscarriage, new study shows
Published 27/09/2016 | 10:17
Morning sickness in pregnant women has been linked to a significantly reduced risk of suffering a miscarriage, new research has found.
A study published in the Journal of the American Medical Association revealed that experiencing nausea and nausea with vomiting was associated with a 50 to 75 per cent reduction in risk of losing a pregnancy.
Morning sickness, which can strike at any point during the day or night, affects roughly eight out of ten women and is thought to be caused by pregnancy hormones which are produced at the highest levels during the first trimester. Experts have said the research should give confidence to women suffering from nausea and vomiting, but stressed that an absence of these symptoms does not necessarily mean a mother will miscarry.
The study by the National Institutes of Health in Maryland analysed the data from nearly 800 women, with an average age of 29, who had suffered one or two previous miscarriages.
The participants were asked to record their symptoms through pregnancy diaries and questionnaires.
Nausea and vomiting were common symptoms even during the earliest weeks of pregnancy, with around one in five women reporting feeling sick even before they had carried out a pregnancy test.
By the second week of gestation, almost 18 per cent had reported nausea without vomiting, while 2.7 per cent said they suffered nausea with vomiting; by week eight the proportions had risen to 57.3 per cent and 26.6 per cent respectively.
The researchers said that, although there has been speculation suggesting that nausea is a sign of a healthy pregnancy, previous evidence has been limited.
“Our study confirms prior research that nausea and vomiting appear to be more than a sign of still being pregnant and instead may be associated with a lower risk for pregnancy loss,” they wrote.
While the study identified a strong correlation between morning sickness and a lower prevalence of miscarriages, the authors were not able to explain the apparent link between the two.
However, some experts have previously said nausea may encourage a healthier pregnancy by leading women to eat less, thereby reducing the risk of exposing the foetus to toxins.
The reduction in food intake also appears to lower levels of circulating insulin and encourage growth of the placenta, research has shown.
A spokesman for the Royal College of Obstetricians and Gynaecologists said: “This new study should provide some reassurance for women suffering from nausea and vomiting that their risk of miscarriage is reduced.
“However, it is important to emphasise that if a woman isn’t suffering from nausea and vomiting, it doesn’t mean she will miscarry.”
Around one in six pregnancies, where the mother to be knows she is pregnant, will end in miscarriage.
Sarah McMullen, from the National Childbirth Trust, said that while pregnant women with morning sickness might be relieved to hear they may have a lower chance of miscarriage, they should not ignore the hazards presented by the condition.
“Vomiting can lead to dehydration and weight loss so women suffering from severe sickness need to keep an eye on their symptoms,” she said.
“If they are unable to keep anything down, they should contact their doctor or midwife immediately."