Midwives should give carbon monoxide tests to all women they see at antenatal appointments, said Britain's National Institute for Health and Clinical Excellence (NICE).
Women found to have high carbon monoxide readings - a sign that they are smoking - will be referred to "smoking cessation services", said the proposed guidance.
Under the guidance, according to The Sunday Times, all discussions about giving up smoking would be recorded in the mother's notes.
An estimated 21 per cent of women smoke during pregnancy.
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This harms foetal growth and development, with smokers three times more likely to have a baby with low birth weight - a leading cause of infant death.
But Royal College of Midwives (RCM) source told The Times the guidance was "ill-judged" and could damage relationships with expectant mothers.
Cathy Warwick, chief executive of the RCM, said the test could help show women the potential damage to unborn babies, but said the final decision must lie with the mother.