Advice says expectant mothers should exercise 2½ hours a week

New exercise advice for pregnant women has been issued by the UK's chief medical officers, aimed at improving the health of expectant mothers and their offspring.

Top tennis player Serena Williams is pregnant. Picture: Peter Parks/AFP/Getty Images

The official recommendations, believed to be the first of their kind in the world, aim to reduce problems such as obesity, diabetes and high blood pressure during pregnancy.

The latest evidence suggests pregnant women should carry out around 150 minutes of moderate-intensity activity every week.

This is described as action that makes you breathe faster but does not stop you being able to hold a conversation.

Those not in the habit of exercising prior to pregnancy are advised to start gently and build up to the weekly target.

However, they are also told to avoid activities that could “bump the bump” and stop if they experience discomfort.

The guidelines are being issued as an infographic, designed to help midwives, nurses, GPs, obstetricians, gynaecologists and fitness professionals give advice for a healthy pregnancy.

Catherine Calderwood, Scotland’s chief medical officer, said: “We want to make pregnant women aware of the benefits of being active throughout their pregnancy and make sure they’re clear about the type of activities that are safe. The latest evidence shows that regular, moderate exercise during pregnancy reduces blood pressure problems, improves fitness, lowers weight gain and reduces the risk of diabetes.

“My advice to pregnant women is to listen to their body and adapt their exercise regime accordingly.

“If you’re not already active, start gradually – and if you are active, just keep going. If anything feels uncomfortable, then stop and seek advice.”

The latest figures suggest one in 20 women is obese during pregnancy. Being overweight increases the risk of complications such as gestational diabetes and the potentially fatal condition pre-eclampsia.

There is also a greater risk of miscarriage, premature birth and interventions such as forceps during delivery.

Midwives have welcomed the new guidelines.

“It is important to keep physically active during pregnancy – moderate exercise will not harm the woman or her baby,” said Louise Silverton, director for midwifery at the Royal College of Midwives (RCM).

She said: “The RCM has consistently advised that being obese when pregnant can cause complications for women and their babies and means we should do all we can to offer support and specialist maternity services for these women.”

At least 18 women have competed in the Olympics while expecting a child.

Tennis star Serena Williams won the Australian Open in January when two months pregnant, while runner Alysia Montaro recently competed in an 800m race at five months pregnant – after doing the same at eight months with her first child in 2014.