Pregnant women will be offered carbon monoxide monitoring to measure exposure to cigarette smoke.

The service, part of the Scottish Patient Safety Maternity Improvement Programme, will be offered to women in the early stages of pregnancy and will indicate raised levels of exposure to the gas through smoking or passive smoking.

Midwives can then refer women to stop smoking support services.

Meanwhile, statistics show that the number of attempts to quit smoking by pregnant women rose last year to 2985, compared with 2756 in 2011.

Smoking 10 or more cigarettes a day in pregnancy doubles the risk of stillbirth, while the risk of cot death increases seven-fold when the mother smokes over 20 a day, particularly if she has smoked in pregnancy, the health service says.

Public Health Minister Michael Matheson said: "We know that giving up smoking is the single best thing anyone can do to improve their health and for women who smoke during pregnancy, quitting is key to improving the health of both mother and baby."