A third of pregnant women smoke and current guidelines recommend that they should be offered intensive support to help them quit. Motivational interviewing - a one to one counselling style designed for treating addictions - is widely taught on smoking cessation training courses but may not apply during pregnancy.
The study took place in Glasgow, Scotland, and involved 762 pregnant women who were regular smokers at antenatal booking. All women received standard health promotion information and 351 were also offered up to five motivational interviews at home with a specially trained midwife.
Levels of cotinine (a by-product of nicotine present in blood and saliva) were measured to verify results in women who reported quitting or cutting down.
There were no significant differences in change in smoking behaviour in the intervention group compared with the control group, although fewer women in the intervention group reported smoking more.
Seventeen (4.8%) of the women in the intervention group stopped smoking compared with 19 (4.6%) in the control group. Fifteen (4.2%) in the intervention group cut down compared with 26 (6.3%) in the control group.
This study gives information to clinicians and policy makers that behavioural intervention alone for those heavily addicted women who continue to smoke at maternity booking is unlikely to be effective enough to provide good value for money, say the authors.
Nicotine replacement therapy is effective in the general population but is not routinely recommended during pregnancy. However, the authors suggest that midwives could provide close supervision of nicotine replacement in women who would not otherwise stop, once safety and effectiveness have been examined.