Financial rewards for pregnant smokers who quitBMJ 2015; 350 doi: https://doi.org/10.1136/bmj.h297 (Published 28 January 2015) Cite this as: BMJ 2015;350:h297
All rapid responses
Felix Naughton has raised a number of issues that contribute to the debate on whether financial incentives should be offered to support smoking cessation in pregnancy. First, he questions whether women understand the risks of smoking in pregnancy and asserts that they underestimate the risks. He is quite correct that women have an incomplete understanding of the pathophysiological mechanisms underlying the adverse effects of smoking in pregnancy. In fact, the precise mechanisms involved in smoking-related placental maladaptation and its effects are poorly understood. The finding that women who stop smoking by 16 weeks’ gestation have pregnancy outcomes similar to non-smokers is counter-intuitive given the importance of early trophoblast invasion on later fetal growth, and the association between smoking and first trimester pregnancy loss. Similarly, the finding that smoking in pregnancy is associated with a reduced risk of pre-eclampsia is difficult to reconcile with our understanding of the mechanisms of fetal growth restriction. What women do understand is that smoking is bad for them and their developing baby, and that if they continue to smoke their baby is likely to be smaller than it should be. Downplaying the risks of unhealthy behaviour is not limited to pregnant smokers.
The second point he raises relates to self-help strategies for smoking cessation. In a prospective cohort study of women booking for antenatal care in an urban Irish setting, we demonstrated that 60% of smokers had quit smoking by the time they attended their first antenatal visit. 1 It is widely reported that pregnant women are self-motivated to stop smoking, and a high proportion succeed on their own. The real challenge lies with the remaining cohort who have no intention of quitting or who fall into a cessation-relapse cycle. These are the women who were targeted in the study by Tappin et al 2 and who represent the population where the greatest gains can be made in addressing preventable perinatal morbidity and mortality.
1. Murphy DJ, Dunney C, Mullally A, Adnan N, Deane R. Population-based study of smoking behaviour throughout pregnancy and adverse perinatal outcomes. Int J Res Public Health 2013;10(9):3855-67.
2. Tappin D, Bauld L, Purves D, Boyd K, Sinclair L, MacAskill S, et al. Financial incentives for smoking cessation in pregnancy: randomised controlled trial. BMJ 2015;350:h134.
Competing interests: No competing interests
Tappin et al’s paper on financial incentives to encourage pregnant smokers to stop smoking with the help of specialist support, is very interesting. The use of incentives could be extrapolated to choosing Planned Caesarean Section (PCS) over Planned Vaginal Birth (PVB)! Here is why …
A recent NICE (1) report presents data that serious adverse outcomes affecting babies born to healthy nulliparous women are equally likely irrespective of planned choice of birth in obstetric units, 'alongside' midwifery units, and freestanding midwifery units. The rate quoted is 5/1000 births (although almost double for planned home births). The breakdown of 'adverse events' provided in the report suggests 1.6/1000 for the incidence of neonatal encephalopathy, which is associated with cerebral palsy (CP). Planned Caesarean Section has the potential to reduce this both by avoiding hypoxia caused by labour and by pre-emptive delivery thereby avoiding late pregnancy catastrophies such as placental abruption or amnionitis.
Another NICE report on Caesarean Section (2) excluded economic considerations other than direct costs in its cost/benefit analysis, and indeed the applicable costs were simply taken from the prevailing Payment By Results (PBR) tariff for care including CS, and care without CS. This distinction has now been abolished in the 2013/2014 PBR tariffs and by this token no additional cost would be ascribed to CS, but even when a CS 'premium' was applied the comparative risks and benefits were such that the report recommended that women should be able to choose PCS subject to provision of appropriate information and offers of counselling. If we take into account wider economic considerations, however, these would be expected to include lifetime care and litigation costs of those cases of CP potentially avoidable by PCS. Taking inflation into account the former may be in the region of £1m (3), whilst the latter may be as high as £5m-£10m per case as evidenced by online searches using the words 'cerebral palsy', 'litigation' and 'settlement'. These figures almost certainly dwarf costs associated with other potential medical risks and benefits of PCS versus PCB.
Estimating the numbers of cases of CP that may be avoided by PCS is difficult, however. One USA study suggests that between 3000 and 5000 PCS procedures may be needed to prevent each case of CP (4). Alternatively if we consider that Spastic Quadriplegia and Dyskinetic encephalopathies are those believed to be most closely related to labour or acute events surrounding it, these are those where litigation risks are likely to be highest due to arguments that they could have been avoided by timely CS. Another large USA study (4) suggests that these encephalopathies account for approximately 25% of cases of neonatal encephalopathy (5). Taking all of this into consideration the range in potential wider economic cost from PVB should be in the region of £200- £3000 when chosen over PCS.
On a similar basis to the author's study might there be an argument therefore to offer healthy women an inducement, perhaps in the region of £500, to choose Planned Caesarean Section. Food for thought!
1. Intrapartum Care: Care of Healthy Women and their Babies during Childbirth. NICE Clinical Guideline 190. December 2014; available online at www.nice.org.uk/guidance/CG190
2. Costing Report accompanying the clinical guideline: 'Caesarean section (partial update of NICE clinical guideline 13)'; available online at www.nice.org.uk/guidance/CG132
3. Kruse M1, Michelsen SI, Flachs EM, Brønnum-Hansen H, Madsen M, Uldall P.Lifetime costs of cerebral palsy. Dev Med Child Neurol. 2009 Aug;51(8):622-8. doi: 10.1111/j.1469-8749.2008.03190.x. Epub 2009 Mar 24.
4. Signore C, Klebanoff M. Neonatal Morbidity and Mortality After Elective Cesarean Delivery. Clinics in perinatology 2008;35(2):361-vi. doi:10.1016/j.clp.2008.03.009.
5. Yeargin-Allsopp M, Van Naarden Braun K, Doernberg NS, Benedict RE, Kirby RS, Durkin MS. Prevalence of cerebral palsy in 8-year-old children in three areas of the United States in 2002: a multisite collaboration. Pediatrics. 2008 Mar;121(3):547-54. doi: 10.1542/peds.2007-1270.
Competing interests: No competing interests
Deirdre Murphy, in her editorial about Tappin and colleagues’ trial of financial incentives for smoking cessation in pregnancy, 1 presents an interesting discussion about the role of financial incentives for changing smoking behaviour in pregnancy.2 Within this piece, Murphy makes two assertions related to other potential mechanisms of smoking behaviour change in pregnancy which I feel motivated to deconstruct to help aid understanding of this behaviour.
Firstly, Murphy states the oft-presented view that the risks of smoking in pregnancy are widely understood by women. Evidence spanning several decades from the UK supports that the vast majority of pregnant women, including smokers, consistently believe that smoking in pregnancy is potentially dangerous to the unborn baby and mother.3,4 However, awareness of the specific effects of smoking during pregnancy appears to be much lower. For example, in their series of nationally representative surveys from the late 1990s, Owen and Penn found that only around half of pregnant smokers agreed that smoking during pregnancy resulted in poisonous chemicals transferred to the baby’s bloodstream and only one in four believed that smoking made the baby’s heart beat faster.4 Among non-smoking pregnant women endorsement in these consequences was not much higher.
We lack data on whether recent public health education efforts have increased awareness of risks of smoking in pregnancy, but recent studies indicate a perhaps more troubling phenomenon regarding risk perception among pregnant smokers. Flemming and colleagues have collated evidence that there is a persistent belief among many pregnant smokers that the risks of harm provided by the media and health professionals have been exaggerated.3 Furthermore, they find that many pregnant smokers challenge the robustness of the evidence of harm from smoking by citing personal experience of instances of prenatal smoking where they do not perceive the offspring to have suffered from health issues. This may be part of a common psychological defensive mechanism where an individual denies or downplays a perceived threat in the face of low perceived control of changing or preventing the source of the threat. Denial or downplaying of threat is common in women who smoke during pregnancy.5,6
The second point made by Murphy that I would like to review is that current cessation treatments for pregnant women include hypnosis and acupuncture. Only one trial of hypnotherapy for pregnant smokers, and none for acupuncture, was identified in the Chamberlain and colleagues Cochrane review cited.7 Hypnosis was poorly accepted by the pregnant participants in this trial and did not demonstrate any evidence of effectiveness. Furthermore there is currently insufficient evidence as to whether hypnotherapy or acupuncture are effective for non-pregnant smokers.8,9
One type of support often overlooked, which usually comes under the umbrella of cognitive and behavioural therapy, is self-help. There is good evidence that self-help is effective for pregnant smokers 10 and is generally of very low cost with high reach potential. Despite this, self-help is not routinely provided to pregnant smokers in the UK. Further research is required for both self-help and financial incentive interventions for pregnant smokers. However, given there are so few effective interventions for pregnant smokers, we cannot afford to delay or ignore interventions with potential for behaviour change as a result of apathy or mixed public opinion.
(1) Tappin D, Bauld L, Purves D, Boyd K, Sinclair L, MacAskill S, et al. Financial incentives for smoking cessation in pregnancy: randomised controlled trial. BMJ 2015;350:h134.
(2) Murphy DJ. Financial rewards for pregnant smokers who quit. BMJ 2015;350:h297.
(3) Flemming K, McCaughan D, Angus K, Graham H. Qualitative systematic review: barriers and facilitators to smoking cessation experienced by women in pregnancy and following childbirth. J Adv Nurs 2014.
(4) Owen L, Penn G. Smoking and Pregnancy: A Survey of Knowledge, Attitudes and Behaviour 1992 - 1999. Health Education Authority; 1999.
(5) Naughton F, Eborall H, Sutton S. Dissonance and disengagement in pregnant smokers: a qualitative study. Journal of Smoking Cessation 2013;8(1):24-32.
(6) Tombor I, Urban R, Berkes T, Demetrovics Z. Denial of smoking-related risk among pregnant smokers. Acta Obstet Gynecol Scand 2010;89(4):524-30.
(7) 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.
(8) White AR, Rampes H, Liu JP, Stead LF, Campbell J. Acupuncture and related interventions for smoking cessation. Cochrane Database Syst Rev 2014;1:CD000009.
(9) Barnes J, Dong CY, McRobbie H, Walker N, Mehta M, Stead LF. Hypnotherapy for smoking cessation. Cochrane Database Syst Rev 2010;(10):CD001008.
(10) Naughton F, Prevost AT, Sutton S. Self-help smoking cessation interventions in pregnancy: a systematic review and meta-analysis. Addiction 2008;103(4):566-79.
Competing interests: No competing interests