Tobacco Smoking in Mother Complicating PregnancySIGSNCT04132232

Smoking Reduction In Gravid Substance Use Disorders

A study testing knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levels in people with Tobacco Smoking in Mother Complicating Pregnancy and Tobacco Use Disorder, run by University of Alabama at Birmingham at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

Search all trials

Trial summary

The aim of this study is to encourage smoking cessation in women with substance use disorders by providing knowledge of expired carbon monoxide. We hypothesize that women who are provided knowledge of their expired carbon monoxide and the associated percent fetal carboxyhemoglobin will have a greater success at… Read more about this study

Who is it for?: Ages 16 to 45 years, women onlyHealthy volunteers can take part
Conditions the study is for: Tobacco Smoking in Mother Complicating Pregnancy, Tobacco Use Disorder, Tobacco Smoking
What is being tested?: knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levels
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 74 participants
Where: 1 siteUnited States
Study dates: 15 Feb 2021to 1 Dec 2023
Phase: Interventional
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 16 to 45 years
Women only
Healthy volunteers accepted
Child, Adult

Who may be able to join

Age 16-45
Singleton gestation
Gestational age at enrollment <24 weeks
Substance use disorder defined as modified National Institute on Drug Abuse ASSIST ≥4
Cigarette smoker using ≥10 cigarettes/day interested in quitting

Who cannot join

Known or suspected fetal growth restriction at enrollment
Known fetal anomaly, aneuploidy, or demise
Not interested in smoking cessation or reduction during pregnancy
E-cigarette use

Trial locations and contacts

1 site in 1 country.

United States1 site

University of Alabama
Birmingham, Alabama, 35233

Other trials in United States

About this study

Official title: Smoking Reduction In Gravid Women With Substance Use Disorders (SIGS): A Randomized Controlled Trial

A secondary aim of the study is to correlate expired carbon monoxide throughout pregnancy with infant birth weight.

Read the detailed description

This is a randomized controlled trial. Pregnant smokers who are substances users who meet inclusion criteria will be offered participation in the study at their first obstetrical appointment. Patients who consent to participate will be randomized.

At the enrollment/randomization visit, women will be randomized to either the intervention (knowledge of and interpretation carbon monoxide levels and associated percent fetal carboxyhemoglobin) or control group (no information on carbon monoxide and associated percent fetal carboxyhemoglobin). Allocation will be computer generated. This will be done after the patient meets all inclusion criteria. If randomization to the intervention arm, the patient will be notified of carbon monoxide and associated fetal carboxyhemoglobin levels at each obstetrical visit and counseled on how it affects maternal and fetal health.

If randomized to the control arm, the patient will have expired carbon monoxide and associated fetal carboxyhemoglobin levels measured at each obstetrical visit but blinded to these results. These patients will not be notified of the levels, nor counseled on what levels mean for maternal or fetal health.

See below for intervention and control protocols.

Maternal demographic (age, race, socioeconomic status), medical history (other medical problems, medications, height, weight) and obstetric history (parity, gestational age) data will be abstracted from the patient's chart and supplemented with a patient questionnaire at the enrollment/randomization visit. The primary outcome is the expired maternal carbon monoxide level at the last obstetric visit or at delivery. This will be determined by the Smokerlyzer device used to measure this. Secondary aims of the study will be to evaluate how maternal carbon monoxide levels correlate with fetal growth, cigarette use per day, patient satisfaction and neonatal birth weight.

All patients will have the following performed at the enrollment/randomization visit and subsequent prenatal visits:

The order of events for all patients will be as follows: i. Blood pressure evaluation ii. Weight iii. Fundal height iv. Patient will be asked the number of cigarettes used per day v. Patient will exhale into Smokerlyzer device to obtain expired carbon monoxide and associated percent fetal carboxyhemoglobin vi. Patients will be provided smoking cessation resources and counseling on smoking cessation in pregnancy

Intervention Protocol

Intervention group will undergo Smokerlyzer ® exhaled carbon monoxide measurements at enrollment, each prenatal visit, and at their last (>36 week) prenatal visit or at delivery if not captured in clinic.
Women will be informed of their exhaled carbon monoxide measurement at each visit as well as the correlation to fetal carboxyhemoglobin.
At each visit, the intervention group will receive counseling on fetal impact of smoking based on fetal carboxyhemoglobin level and institutional and state information on smoking cessation will be provided.
The patient will then proceed to the remainder of the obstetrical visit.

Control Protocol

Women in the control group will undergo Smokerlyzer ® exhaled carbon monoxide measurements at enrollment, each prenatal visit and at their final (>36 week) prenatal visit or at delivery if not captured in clinic.
Both levels (maternal carbon monoxide and fetal carboxyhemoglobin) will be recorded by the co-investigatory, but NOT disclosed to the patient
At each visit, control group will be provided institutional and state information on smoking cessation if they report continued smoking.
The patient will then proceed to remainder of the obstetrical visit.

For both groups:

At the time of delivery, maternal and neonatal outcome data will be recorded from the chart, including gestational age at delivery, mode of delivery, indications for delivery, birth weight, Apgar score, cord blood gas, length of stay, and neonatal complications, if any. A survey will be completed for both intervention and standard care groups after delivery.

Conditions: Tobacco Smoking in Mother Complicating Pregnancy, Tobacco Use Disorder, Tobacco Smoking
Being tested: knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levels
Keywords: smoking in pregnancy, substance use disorder, carbon monoxide, fetal carboxyhemoglobin
Medical subject headings: Tobacco Use Disorder, Tobacco Smoking, Substance-Related Disorders

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levelsDiagnostic test
Also called adverse outcomes related to expired maternal carbon monoxide and fetal carboxyhemoglobin levels
Will use the Smokerlyzer® device at each visit and be provided information on exhaled carbon monoxide and fetal carboxyhemoglobin. Risks of adverse perinatal outcomes related to maternal carbon monoxide and fetal carboxyhemoglobin level will be provided.

Study groups in NCT04132232
Study group	Role	What they receive
Treatment Group	Experimental	1. The patient will exhaled into the Smokerlyzer® device will at each visit 2. Exhaled carbon monoxide and fetal carboxyhemoglobin levels will be disclosed to the patient 3. Risks of adverse perinatal outcomes related to maternal carboxyhemoglobin and fetal carboxyhemoglobin level will be provided. Receives: Diagnostic Test: knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levels
Control Group	No intervention	1. The patient will exhale into the Smokerlyzer® device at each visit. 2. Exhaled carbon monoxide and fetal carboxyhemoglobin level will NOT be disclosed to the patient 3. No risks of adverse perinatal outcomes related to maternal carbon monoxide and fetal carboxyhemoglobin levels will be provided

What is being measured

The primary outcome is the main question the study is designed to answer.

Prevalence of Smoking ≥ 10 Cigarettes/Day in Each Group at Final Measurement by Exhaled Carbon Monoxide Level
Prevalence of smoking ≥ 10 cigarettes/day in each group at final measurement by exhaled carbon monoxide level at last prenatal visit prior to delivery, as measured by exhaled carbon monoxide
Measured: Final measurement (last prenatal care visit or at delivery)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

15 Feb 20211 Dec 2023

First posted18 Oct 2019
Study start15 Feb 2021
Primary completion1 Dec 2023
Study completion1 Dec 2023

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (14)Papers the sponsor has linked to this study.
Other trials for Tobacco Smoking in Mother Complicating PregnancyStudies of the same condition, open and under way.
More trials run by University of Alabama at BirminghamThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase N/A
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Model description: Randomized controlled trial
Masking: Single blind
Who is masked: Participant
Enrolment: 74 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT04132232
Sponsor's protocol ID: SIGS
Other IDs: JCHF, UAB
Acronym: SIGS
Status last verified: Feb 2024
First submitted: 12 Oct 2019
Last updated: 5 Aug 2024
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No
Individual data sharing: No

Publications

Sandberg A, Skold CM, Grunewald J, Eklund A, Wheelock AM. Assessing recent smoking status by measuring exhaled carbon monoxide levels. PLoS One. 2011;6(12):e28864. doi: 10.1371/journal.pone.0028864. Epub 2011 Dec 16.
PubMed 22194931
Bedfont. Smokerlyzer range user manual. http://www.bedfont.com/file.php?f=ZmlsZSMjMTgxMg. Updated 2019. Accessed Sept 16, 2016.
Gomez C, Berlin I, Marquis P, Delcroix M. Expired air carbon monoxide concentration in mothers and their spouses above 5 ppm is associated with decreased fetal growth. Prev Med. 2005 Jan;40(1):10-5. doi: 10.1016/j.ypmed.2004.04.049.
PubMed 15530575
Goldstein AO, Gans SP, Ripley-Moffitt C, Kotsen C, Bars M. Use of Expired Air Carbon Monoxide Testing in Clinical Tobacco Treatment Settings. Chest. 2018 Feb;153(2):554-562. doi: 10.1016/j.chest.2017.11.002. Epub 2017 Nov 11.
PubMed 29137909
Riaz M, Lewis S, Coleman T, Aveyard P, West R, Naughton F, Ussher M. Which measures of cigarette dependence are predictors of smoking cessation during pregnancy? Analysis of data from a randomized controlled trial. Addiction. 2016 Sep;111(9):1656-65. doi: 10.1111/add.13395. Epub 2016 May 6.
PubMed 26997495
Jha P, Ramasundarahettige C, Landsman V, Rostron B, Thun M, Anderson RN, McAfee T, Peto R. 21st-century hazards of smoking and benefits of cessation in the United States. N Engl J Med. 2013 Jan 24;368(4):341-50. doi: 10.1056/NEJMsa1211128.
PubMed 23343063
QuickStats: Number of Deaths from 10 Leading Causes,* by Sex - National Vital Statistics System, United States, 2015. MMWR Morb Mortal Wkly Rep. 2017 Apr 21;66(15):413. doi: 10.15585/mmwr.mm6615a8.
PubMed 28426642
Middleton ET, Morice AH. Breath carbon monoxide as an indication of smoking habit. Chest. 2000 Mar;117(3):758-63. doi: 10.1378/chest.117.3.758.
PubMed 10713003
McClure JB. Are biomarkers a useful aid in smoking cessation? A review and analysis of the literature. Behav Med. 2001 Spring;27(1):37-47. doi: 10.1080/08964280109595770.
PubMed 11575171
11. Bedfont. Smokerlyzer range user manual. http://www.bedfont.com/file.php?f=ZmlsZSMjMTgxMg. Updated 2019. Accessed Sept 16, 2019.
Shahab L, West R, McNeill A. A randomized, controlled trial of adding expired carbon monoxide feedback to brief stop smoking advice: evaluation of cognitive and behavioral effects. Health Psychol. 2011 Jan;30(1):49-57. doi: 10.1037/a0021821.
PubMed 21299294
Bize R, Burnand B, Mueller Y, Rege-Walther M, Camain JY, Cornuz J. Biomedical risk assessment as an aid for smoking cessation. Cochrane Database Syst Rev. 2012 Dec 12;12:CD004705. doi: 10.1002/14651858.CD004705.pub4.
PubMed 23235615
Reynolds CME, Egan B, Kennedy RA, O'Malley E, Sheehan SR, Turner MJ. The implications of high carbon monoxide levels in early pregnancy for neonatal outcomes. Eur J Obstet Gynecol Reprod Biol. 2019 Feb;233:6-11. doi: 10.1016/j.ejogrb.2018.11.020. Epub 2018 Nov 30.
PubMed 30529257
Ecker J, Abuhamad A, Hill W, Bailit J, Bateman BT, Berghella V, Blake-Lamb T, Guille C, Landau R, Minkoff H, Prabhu M, Rosenthal E, Terplan M, Wright TE, Yonkers KA. Substance use disorders in pregnancy: clinical, ethical, and research imperatives of the opioid epidemic: a report of a joint workshop of the Society for Maternal-Fetal Medicine, American College of Obstetricians and Gynecologists, and American Society of Addiction Medicine. Am J Obstet Gynecol. 2019 Jul;221(1):B5-B28. doi: 10.1016/j.ajog.2019.03.022. Epub 2019 Mar 27. No abstract available.
PubMed 30928567

Study at a glance

From the registry record, last updated by the sponsor on 5 Aug 2024. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Smoking Reduction In Gravid Women With Substance Use Disorders (SIGS): A Randomized Controlled Trial
ClinicalTrials.gov ID: NCT04132232
Acronym / sponsor ID: SIGS / SIGS
Conditions: Tobacco Smoking in Mother Complicating Pregnancy, Tobacco Use Disorder, Tobacco Smoking
Keywords: smoking in pregnancy, substance use disorder, carbon monoxide, fetal carboxyhemoglobin
Study type: Interventional
Recruitment status: Completed
Enrolment: 74 participants (actual)
Lead sponsor: University of Alabama at BirminghamUniversity, hospital or other
Study start: 15 Feb 2021 (actual)
Primary completion: 1 Dec 2023 (actual)
Study completion: 1 Dec 2023 (actual)
First posted: 18 Oct 2019 (actual)
Results: Posted 5 Aug 2024

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

A secondary aim of the study is to correlate expired carbon monoxide throughout pregnancy with infant birth weight.

Detailed description

See below for intervention and control protocols.

All patients will have the following performed at the enrollment/randomization visit and subsequent prenatal visits:

The order of events for all patients will be as follows: i. Blood pressure evaluation ii. Weight iii. Fundal height iv. Patient will be asked the number of cigarettes used per day v. Patient will exhale into Smokerlyzer device to obtain expired carbon monoxide and associated percent fetal carboxyhemoglobin vi. Patients will be provided smoking cessation resources and counseling on smoking cessation in pregnancy

Intervention Protocol

Intervention group will undergo Smokerlyzer ® exhaled carbon monoxide measurements at enrollment, each prenatal visit, and at their last (>36 week) prenatal visit or at delivery if not captured in clinic.
Women will be informed of their exhaled carbon monoxide measurement at each visit as well as the correlation to fetal carboxyhemoglobin.
At each visit, the intervention group will receive counseling on fetal impact of smoking based on fetal carboxyhemoglobin level and institutional and state information on smoking cessation will be provided.
The patient will then proceed to the remainder of the obstetrical visit.

Control Protocol

Women in the control group will undergo Smokerlyzer ® exhaled carbon monoxide measurements at enrollment, each prenatal visit and at their final (>36 week) prenatal visit or at delivery if not captured in clinic.
Both levels (maternal carbon monoxide and fetal carboxyhemoglobin) will be recorded by the co-investigatory, but NOT disclosed to the patient
At each visit, control group will be provided institutional and state information on smoking cessation if they report continued smoking.
The patient will then proceed to remainder of the obstetrical visit.

For both groups:

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Single blind (participant)
Number of arms: 2
Model description: Randomized controlled trial

Arm	Type	Receives
Treatment Group	Experimental	Diagnostic Test: knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levels1. The patient will exhaled into the Smokerlyzer® device will at each visit 2. Exhaled carbon monoxide and fetal carboxyhemoglobin levels will be disclosed to the patient 3. Risks of adverse perinatal outcomes related to maternal carboxyhemoglobin and fetal carboxyhemoglobin level will be provided.
Control Group	No intervention	–1. The patient will exhale into the Smokerlyzer® device at each visit. 2. Exhaled carbon monoxide and fetal carboxyhemoglobin level will NOT be disclosed to the patient 3. No risks of adverse perinatal outcomes related to maternal carbon monoxide and fetal carboxyhemoglobin levels will be provided

Who may qualify

Ages: 16 to 45 years
Sex: Female only
Healthy volunteers: Accepted
Age groups: Child, Adult

Key inclusion criteria (5 listed)

Age 16-45
Singleton gestation
Gestational age at enrollment <24 weeks
Substance use disorder defined as modified National Institute on Drug Abuse ASSIST ≥4
Cigarette smoker using ≥10 cigarettes/day interested in quitting

Key exclusion criteria (4 listed)

Known or suspected fetal growth restriction at enrollment
Known fetal anomaly, aneuploidy, or demise
Not interested in smoking cessation or reduction during pregnancy
E-cigarette use

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
knowledge of expired maternal carbon monoxide and fetal carboxyhemoglobin levelsAlso: adverse outcomes related to expired maternal carbon monoxide and fetal carboxyhemoglobin levelsWill use the Smokerlyzer® device at each visit and be provided information on exhaled carbon monoxide and fetal carboxyhemoglobin. Risks of adverse perinatal outcomes related to maternal carbon monoxide and fetal carboxyhemoglobin level will be provided.	Diagnostic test	Treatment Group

Primary outcome

Prevalence of Smoking ≥ 10 Cigarettes/Day in Each Group at Final Measurement by Exhaled Carbon Monoxide Level
Time frame: Final measurement (last prenatal care visit or at delivery)
Prevalence of smoking ≥ 10 cigarettes/day in each group at final measurement by exhaled carbon monoxide level at last prenatal visit prior to delivery, as measured by exhaled carbon monoxide

Results and safety

Results posted to the registry on 5 Aug 2024, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Treatment Group	37	30
Control Group	37	29

Primary outcome: Prevalence of Smoking ≥ 10 Cigarettes/Day in Each Group at Final Measurement by Exhaled Carbon Monoxide Level

Time frame: Final measurement (last prenatal care visit or at delivery). Number. Unit: participants

Measure	Treatment Group n = 37	Control Group n = 36
Value	22	16

Treatment Group vs Control Group: p = 0.06, Chi-squared

Population analysed: Participants who had expired carbon monoxide measured at either their last prenatal visit or at delivery.

Adverse events

Time frame: Over the course of the study period, which is around 10 months per participant.. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Treatment Group	0 of 37 (0%)	0 of 37 (0%)	0 of 37
Control Group	0 of 37 (0%)	0 of 37 (0%)	0 of 37

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 5 Aug 2024.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Background: PubMed 22194931Sandberg A, Skold CM, Grunewald J, Eklund A, Wheelock AM. Assessing recent smoking status by measuring exhaled carbon monoxide levels. PLoS One. 2011;6(12):e28864. doi: 10.1371/journal.pone.0028864. Epub 2011 Dec 16.
BackgroundBedfont. Smokerlyzer range user manual. http://www.bedfont.com/file.php?f=ZmlsZSMjMTgxMg. Updated 2019. Accessed Sept 16, 2016.
Background: PubMed 15530575Gomez C, Berlin I, Marquis P, Delcroix M. Expired air carbon monoxide concentration in mothers and their spouses above 5 ppm is associated with decreased fetal growth. Prev Med. 2005 Jan;40(1):10-5. doi: 10.1016/j.ypmed.2004.04.049.
Background: PubMed 29137909Goldstein AO, Gans SP, Ripley-Moffitt C, Kotsen C, Bars M. Use of Expired Air Carbon Monoxide Testing in Clinical Tobacco Treatment Settings. Chest. 2018 Feb;153(2):554-562. doi: 10.1016/j.chest.2017.11.002. Epub 2017 Nov 11.
Background: PubMed 26997495Riaz M, Lewis S, Coleman T, Aveyard P, West R, Naughton F, Ussher M. Which measures of cigarette dependence are predictors of smoking cessation during pregnancy? Analysis of data from a randomized controlled trial. Addiction. 2016 Sep;111(9):1656-65. doi: 10.1111/add.13395. Epub 2016 May 6.
Background: PubMed 23343063Jha P, Ramasundarahettige C, Landsman V, Rostron B, Thun M, Anderson RN, McAfee T, Peto R. 21st-century hazards of smoking and benefits of cessation in the United States. N Engl J Med. 2013 Jan 24;368(4):341-50. doi: 10.1056/NEJMsa1211128.
Background: PubMed 28426642QuickStats: Number of Deaths from 10 Leading Causes,* by Sex - National Vital Statistics System, United States, 2015. MMWR Morb Mortal Wkly Rep. 2017 Apr 21;66(15):413. doi: 10.15585/mmwr.mm6615a8.
Background: PubMed 10713003Middleton ET, Morice AH. Breath carbon monoxide as an indication of smoking habit. Chest. 2000 Mar;117(3):758-63. doi: 10.1378/chest.117.3.758.
Background: PubMed 11575171McClure JB. Are biomarkers a useful aid in smoking cessation? A review and analysis of the literature. Behav Med. 2001 Spring;27(1):37-47. doi: 10.1080/08964280109595770.
Background11. Bedfont. Smokerlyzer range user manual. http://www.bedfont.com/file.php?f=ZmlsZSMjMTgxMg. Updated 2019. Accessed Sept 16, 2019.
Background: PubMed 21299294Shahab L, West R, McNeill A. A randomized, controlled trial of adding expired carbon monoxide feedback to brief stop smoking advice: evaluation of cognitive and behavioral effects. Health Psychol. 2011 Jan;30(1):49-57. doi: 10.1037/a0021821.
Background: PubMed 23235615Bize R, Burnand B, Mueller Y, Rege-Walther M, Camain JY, Cornuz J. Biomedical risk assessment as an aid for smoking cessation. Cochrane Database Syst Rev. 2012 Dec 12;12:CD004705. doi: 10.1002/14651858.CD004705.pub4.
Smokerlyzer product websiteLink provided by the sponsor.
Individual participant dataSharing planned: No

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Rachel G Sinkey, MD principal investigator

University of Alabama at Birmingham

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 5 Aug 2024. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

Yes. Results are posted in the registry (first posted 5 Aug 2024). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Prevalence of Smoking ≥ 10 Cigarettes/Day in Each Group at Final Measurement by Exhaled Carbon Monoxide Level (time frame: Final measurement (last prenatal care visit or at delivery)). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04132232, which also lists 14 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Aug 2024; AzTrials last refreshed its copy on 26 Oct 2026.