Can a specialised antenatal clinic help pregnant women quit smoking and reduce the risk of complications for mother and baby?

• Register: ISRCTN
• Last refreshed on: 7 November 2022
• Main ID: ISRCTN11214785
• Date of registration: 08/02/2018
• Prospective Registration: Yes
• Primary sponsor: Royal College of Surgeons in Ireland
• Public title: Can a specialised antenatal clinic help pregnant women quit smoking and reduce the risk of complications for mother and baby?
• Scientific title: Smoking cessation Through Optimisation of clinical care in Pregnancy - the STOP trial
• Date of first enrolment: 12/02/2018
• Target sample size: 450
• Recruitment status: Completed
• URL: https://www.isrctn.com/ISRCTN11214785
• Study type: Interventional
• Study design: Single-centre pragmatic randomised controlled trial (Prevention)
• Phase: Not Applicable

Countries of recruitment

Ireland

Contacts

• Name: Brendan McDonnell

Key inclusion & exclusion criteria

Inclusion criteria:
1. = 18yrs old
2. Singleton pregnancy
3. Smoking = 1 cigarette daily
4. English language spoken

Exclusion criteria:
1. Significant maternal medical disorder, eg. cardiac, haematological or endocrine disease (including GDM on metformin or insulin) requiring specialised maternal antenatal care.
2. Significant maternal psychiatric disorder, eg. delusional or psychotic disorders, severe depression requiring hospitalisation, use of =2 psychotropic drugs for treatment.
3. Serious co-morbid addiction issues eg opiate abuse, methadone maintenance program
4. Positive serology requiring specialised antenatal care
5. Significant fetal anomaly defined as aneuploidy, life limiting or lethal fetal anomaly
6. Intellectual disability or lack of capacity
7. Poor English / No English


Age minimum:
Age maximum:
Gender: Female

Health Condition(s) or Problem(s) studied

Smoking in pregnancy
Pregnancy and Childbirth
Smoking in pregnancy

Intervention(s)

Current intervention as of 06/12/2018:
Women who smoke in pregnancy are randomised at first visit to either the STOP clinic or 'routine care'.

In the STOP clinic, they have consultant-led antenatal care with the addition of a dedicated smoking cessation practitioner who is in-built into the clinic. As smokers are at risk of late-onset intrauterine growth restriction (IUGR) they are scanned at 32 and 36 weeks gestation. 225 women are assigned to the intervention arm and 226 to 'routine care' - 113 of the routine care group receive the additional scans at 32 and 36 weeks, and 113 who do not receive any additional scans.

Smoking status is biologically quantified and measured at each visit. They receive smoking cessation reviews at booking visit, 1 week post quit date, 4 weeks, 3 months and 6 months or end of pregnancy. A final cessation status is recorded in the postnatal period.

Previous intervention:
Women who smoke in pregnancy are randomised at first visit to either the STOP clinic or a pre-defined 'routine care'.

In the STOP clinic, they have consultant led antenatal care with the addition of a dedicated smoking cessation practitioner who is in-built into the clinic. As smokers are at risk of late-onset intrauterine growth restriction (IUGR) they are scanned at 32 and 36 weeks gestation. 300 women are assigned to the intervention arm and 300 to pre-defined 'routine care' - 150 of the routine care group receive the additional scans at 32 and 36 weeks, and 150 who do not receive any additional scans.

Smoking status is biologically quantified and measured at each visit. They receive smoking cessation reviews at booking visit, one

Primary Outcome(s)

Self-reported continuous abstinence from smoking between the quit date and end of pregnancy (quit date is targeted as being at or before 16 weeks gestation and no further than 28 weeks gestation). This is validated using the exhaled carbon monoxide (CO) or urinary cotinine measured at one week, four weeks, three months and six months post quit date.

Secondary Outcome(s)

1. Reduced cigarette intake at 3 months post quit date, 6 months post quit date, end of pregnancy and at 6 months postpartum, validated using the exhaled carbon monoxide (CO) or urinary cotinine
2. Urge to smoke, measured using behavioural questionnaire at the end of pregnancy and 6 months after the birth
3. Tobacco withdrawal symptoms, measured using behavioural questionnaire at end of pregnancy and 6 months after the birth
4. Self- confidence in stopping smoking, measured using behavioural questionnaire at end of pregnancy and 6 months after the birth
5. Self-reported depression, measured using questionnaire at end of pregnancy and 6 months after the birth
6. Fetal morbidity and mortality outcomes are prospectively collected:
6.1. Miscarriage
6.2. Stillbirth
6.3. Neonatal death
6.4. Birth weight
6.5. Estimated fetal weight at 32 weeks
6.6. Estimated fetal weight at 36 weeks
6.7. Spontaneous pre-term birth
6.8. Iatrogenic pre-term birth
6.9. Birth injury
6.10. Neonatal complication
6.11. Oxygen dependence
6.12. Admission to neonatal unit
6.13. Length of stay of neonate
7. Maternal morbidity and mortality outcomes are prospectively collected:
7.1. Maternal death
7.2. Mode of delivery
7.3. Need for induction/delivery
7.4. Maternal need for intensive care
7.5. Maternal length of stay
7.6. Pre-eclampsia
7.7. Pregnancy induced hypertension
7.8. Postpartum haemorrhage
7.9. Blood transfusion
7.10. Late maternal complication
8. Satisfaction with results of care, measured using questionnaire in postnatal period
9. Confidence as an active participant in health care decisions, measured using questionnaire in postnatal period
10. Confidence in healthcare providers, measured using questionnaire in postnatal period
11. Birth experience, measured using questionnaire in postnatal period

Secondary ID(s)

STOPtrial

Source(s) of Monetary Support

Friends of the Coombe

Secondary Sponsor(s)

Coombe Women and Infants University Hospital

Ethics review

Status:
Approval date:
Contact:

Coombe Women and Infants University Hospital Research and Ethics Committee, 10/01/2018, ref: Study 25-2017

Results

• Results available: Yes
• Date Completed: 31/12/2020