The study involved 128 midwives working in three NHS trusts in England and 1,527 women who smoked at the start of pregnancy. Half the women received normal antenatal care (normal care group) and half received the Stop for Good self-help programme in addition to normal care (intervention group). All women were surveyed 26 weeks into their pregnancy. Those who said they had not smoked for at least seven days supplied a urine sample for validation.
Validated smoking cessation rates were low: 19% in the intervention group and 21% in the normal care group. Self reported quit rates were higher. In the intervention group, 26% of women reported not smoking for at least seven days, compared with 29% in the normal care group.
Although the self-help programme was acceptable to midwives and pregnant women, it failed to affect smoking behaviour at the end of the second trimester of pregnancy, say the authors. More intensive and complex interventions, appropriately targeted and tailored, need to be developed and evaluated.
The discrepancy between validated and self reported quit rates calls into question the adequacy of monitoring of the government's target for smoking in pregnancy, which currently relies on retrospective self-reported smoking behaviour, say the authors. Validated rates among pregnant women are substantially lower than the self-reported rates on which current smoking policy is based, they conclude.