title: Physical activity for smoking cessation in pregnancy: randomised controlled trial.
abstract: OBJECTIVE
  To determine the effectiveness of a physical activity intervention for smoking cessation during pregnancy.
  
  
  METHODS
  Parallel group, randomised controlled, multicentre trial.
  
  
  METHODS
  13 hospitals in England, April 2009 to January 2014.
  
  
  METHODS
  789 pregnant smokers, aged 16-50 years and at 10-24 weeks' gestation, who smoked at least one cigarette daily and were prepared to quit smoking one week after enrollment were randomised (1:1); 785 were included in the intention to treat analyses, with 392 assigned to the physical activity group.
  
  
  METHODS
  Interventions began one week before a target quit date. Participants were randomised to six weekly sessions of behavioural support for smoking cessation (control) or to this support plus 14 sessions combining supervised treadmill exercise and physical activity consultations.
  
  
  METHODS
  The primary outcome was continuous smoking abstinence from the target quit date until end of pregnancy, validated by exhaled carbon monoxide or salivary cotinine levels. To assess adherence, levels of moderate-vigorous intensity physical activity were self reported and in a 11.5% (n=90) random subsample of participants, physical activity was objectively measured by an accelerometer.
  
  
  RESULTS
  No significant difference was found in rates of smoking abstinence at end of pregnancy between the physical activity and control groups (8% v 6%; odds ratio 1.21, 95% confidence interval 0.70 to 2.10). For the physical activity group compared with the control group, there was a 40% (95% confidence interval 13% to 73%), 34% (6% to 69%), and 46% (12% to 91%) greater increase in self reported minutes carrying out physical activity per week from baseline to one week, four weeks, and six weeks post-quit day, respectively. According to the accelerometer data there was no significant difference in physical activity levels between the groups. Participants attended a median of four treatment sessions in the intervention group and three in the control group. Adverse events and birth outcomes were similar between the two groups, except for significantly more caesarean births in the control group than in the physical activity group (29% v 21%, P=0.023).
  
  
  CONCLUSIONS
  Adding a physical activity intervention to behavioural smoking cessation support for pregnant women did not increase cessation rates at end of pregnancy. During pregnancy, physical activity is not recommended for smoking cessation but remains indicated for general health benefits. Trial registration Current Controlled Trials ISRCTN48600346.
authors.affiliation: Population Health Research Institute, St George's University of London, London SW17 ORE, UK mussher@sgul.ac.uk.
authors.forename: Michael
authors.initials: M
authors.lastname: Ussher
authors.affiliation: Division of Epidemiology and Public Health and UK Centre for Tobacco and Alcohol Studies, University of Nottingham, Nottingham, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Lewis
authors.affiliation: Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Aveyard
authors.affiliation: Department of Obstetrics and Gynaecology, St George's University of London and St George's NHS Trust, London, UK.
authors.forename: Isaac
authors.initials: I
authors.lastname: Manyonda
authors.affiliation: Health Behaviour Research Centre, Department of Epidemiology and Public Health, University College London, London, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: West
authors.affiliation: School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Beth
authors.initials: B
authors.lastname: Lewis
authors.affiliation: Department of Family and Preventive Medicine, University of California, San Diego, CA, USA.
authors.forename: Bess
authors.initials: B
authors.lastname: Marcus
authors.affiliation: Population Health Research Institute, St George's University of London, London SW17 ORE, UK.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Riaz
authors.affiliation: Plymouth University Peninsula Schools of Medicine and Dentistry, Plymouth, Devon, UK.
authors.forename: Adrian
authors.initials: A
authors.lastname: Taylor
authors.affiliation: Primary Care Clinical Sciences, University of Birmingham, Birmingham, UK.
authors.forename: Amanda
authors.initials: A
authors.lastname: Daley
authors.affiliation: Division of Primary Care and UK Centre for Tobacco and Alcohol Studies, University of Nottingham, Nottingham, UK.
authors.forename: Tim
authors.initials: T
authors.lastname: Coleman
mesh_terms: D000293:Adolescent; D000328:Adult; D001521:Behavior Therapy; D003131:Combined Modality Therapy; D004739:England / Q000453:epidemiology; D005081:Exercise Therapy; D005260:Female; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D007231:Infant, Newborn; D033182:Intention; D008875:Middle Aged; D009042:Motivation; D010349:Patient Compliance; D011247:Pregnancy; D011295:Prenatal Care / Q000379:methods*; D012907:Smoking / Q000453:epidemiology / Q000523:psychology; D016540:Smoking Cessation / Q000379:methods; D000074606:Smoking Prevention; D012944:Social Support; D016896:Treatment Outcome