Putting your feet up while pregnant could be harmful for both mother and baby, say scientists.

Experts have warned that bed rest during pregnancy has few benefits – and can lead to depression, muscle loss, and a greater risk of blood clots and diabetes, The Daily Mail reports.

It could also result in babies having a lower weight at birth

Issuing key guidelines, the Society for Maternal-Fetal Medicine in America said that around one in five women in the US is put on bed rest during pregnancy, often as a result of complications.

However, it said, it no longer recommends routinely limiting physical activity.

Co-author Anthony Sciscione, of the Delaware Centre for Maternal and Fetal Medicine, said: ‘There is no evidence bed rest improves outcomes.

‘However there is evidence bed rest can be harmful for moms, babies and families.’

Surveys show that obstetricians and gynaecologists often prescribe bed rest even though most do not believe it will do much to improve outcomes for women.

It is prescribed for a variety of complications ranging from premature contractions or early labour to high blood pressure, potentially fatal pre-eclampsia, inadequate growth of the baby and for women who are at high risk of miscarriage.

But the Society said bed rest has not been shown to reduce the chance of a premature delivery, either for women who are thought to be at risk or for those already in early labour.

One study found premature birth actually became more common when at-risk women were placed on any type of activity restriction – either at home or in hospital. There is little data to show activity restriction is of benefit for any condition linked to pregnancy, Dr Sciscione said.

For example, bed rest is often prescribed in an attempt to increase the blood flow to the placenta when the baby is not growing fast enough

But studies fail to show any benefit to this practice.

At the same time, there are several potentially harmful side effects of bed rest.

It is widely known that doing too little activity can result in muscle and bone loss.

Bed rest may also increase the risk of developing blood clots in the legs – and raise the chance that clots will move to the lungs, which can be fatal.

Such clots are more common among pregnant women, so limiting physical activity may compound these risks.

Lack of movement may also increase a woman’s risk of gestational diabetes.

Bed rest also increases the risk of anxiety and depression, perhaps because of the forced inactivity.