All the pregnant women attending for consultation with the midwives of the four PC teams involved during the study period, who are smoking at least one cigarette a day when they find out they are pregnant and who want to take part in the study once they have been informed of it. Intervention. The subjects included will be randomised into 2 intervention groups. The minimum intervention will consist of brief personal counselling (3 to 5 minutes) on why they should give up smoking, especially now they are pregnant. The group intervention will involve 3 sessions lasting approximately an hour and a half.