Smoking during pregnancy is thought to cause approximately 25,000 miscarriages per year in the United Kingdom (Health and Social Care Information Centre, 2010).

Additionally, smoking while pregnant is attributable to 4-7% of stillbirths (Flenady et al., 2011), and 3-5% of infant deaths (Gray et al., 2009) with these rates even higher in deprived areas, where remaining a smoker during pregnancy is more common (Gray et al., 2009).

In 2009, 24% of women attending antenatal appointments in Scotland were smokers (NHS, 2009). However only 1 in 10 reported using cessation services, and 3% were abstaining by four weeks (Tappin et al., 2010).

A recent Cochrane systematic review suggested financial incentives may be beneficial in helping pregnant women stop smoking, although it concluded that further evidence was needed (Chamberlain et al., 2013). Tappin et al (2015) investigated the effectiveness of shopping vouchers in addition to NHS Stop Smoking Services to aid quit attempts in pregnant women.

Methods 

The authors conducted a randomised controlled trial of 609 pregnant smokers recruited from NHS Greater Glasgow and Clyde. Women were randomly allocated to routine smoking cessation care (control group) or to routine care and up to £400 in shopping vouchers if they engaged with services and successfully quit smoking (incentives group).

Routine care

Routine specialist pregnancy care involved an initial meeting to discuss quitting smoking and set a quit date. This was followed by 4 weekly telephone calls, and free nicotine replacement therapy for 10 weeks.

Incentives group

The incentives group received £50 in shopping vouchers for attending the initial meeting to set a quit date. If participants were smoke-free 4 weeks later, they would receive another £50 voucher, and if smoke-free at 12 weeks, participants received £100 in gift vouchers. Between 34-38 weeks gestation, women were once again asked smoking status, and those who had quit received a final £200 voucher. In all instances, smoking status was verified by a carbon monoxide breath test. 

Results 

• More women successfully quit smoking in the incentives group (22.5%) than the routine care group (8.6%).
• There was a higher quit rate at 4 weeks in the incentives group compared to the routine care group.
• 12 months after quit date, there was still large difference in self-reported quit rates (15% incentives, 4% control).
• Women lost to follow-up were assumed to be smokers, which was validated by analysing residual routine blood samples for cotinine.

Summary

This study demonstrated that financial incentives with routine care could be beneficial in motivating quit attempts in pregnant smokers, as well as aiding them in continuing to abstain up to 12 months after their quit date. Furthermore, the quit rates reported in this trial were larger than many pharmaceutical (Coleman et al., 2012) or behavioural (Chamberlain et al., 2013) intervention trials in pregnant women. Although, it should be noted that women in the control group had higher nicotine addiction scores than those in the incentives group.

While the evidence from this study suggests using financial incentives may be beneficial in helping pregnant smokers to stop, there may be practical and ethical issues in implementing this as an intervention.

Additionally, other studies are needed to determine the generalizability and possible cost effectiveness of this intervention, as well as what cessation services are best suited to pair with financial incentives. However, it will be interesting to see how this study may be used to inform future policy.

Links

Tappin D, Bauld L, Purves D, Boyd K, Sinclair L, MacAskill S et al. Financial incentives for smoking cessation in pregnancy: randomised controlled trial (pdf). BMJ 2015; 350:h134

Health and Social Care Information Centre, Infant feeding survey 2010 (pdf). HSCIC, 2012. www.hscic.gov.uk/pubs/ifs2005.

Flenady V, Koopmans L, Middleton P, Frøen JF, Smith GC, Gibbons K, et al. Major risk factors for stillbirth in high-income countries: a systematic review and meta-analysis. Lancet 2011;377:1331-40. [Abstract]

Gray R, Bonellie SR, Chalmers J, Greer I, Jarvis S, Kurinczuk J, et al. Contribution of smoking during pregnancy to inequalities in stillbirth and infant death in Scotland 1994-2003: retrospective population based study using hospital maternity records. BMJ 2009;339:b3754.

Information Services Division, NHS National Services Scotland. Births and babies: smoking and pregnancy, 2009. www.isdscotland.org/isd/2911.html.

Tappin DM, MacAskill S, Bauld L, Eadie D, Shipton D, Galbraith L. Smoking prevalence and smoking cessation services for pregnant women in Scotland. Subst Abuse Treat Prev Policy 2010;5:1.

Coleman T, Chamberlain C, Davey MA, Cooper SE, Leonardi-Bee J. Pharmacological interventions for promoting smoking cessation during pregnancy. Cochrane Database Syst Rev 2012;9:CD010078. [Abstract]

Chamberlain C, O’Mara-Eves A, Oliver S, Caird JR, Perlen SM, Eades SJ, et al. Psychosocial interventions for supporting women to stop smoking in pregnancy. Cochrane Database Syst Rev 2013;10:CD001055