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Cited by 74Smoking Behavior and CessationPrenatal Substance Exposure EffectsMaternal and Neonatal Healthcare

Adverse Birth Outcomes Associated With Prepregnancy and Prenatal Electronic Cigarette Use

Open access
Regan, Annette K., Bombard, Jennifer M., O’Hegarty, Michelle M., Smith, Ruben A., Tong, Van T.·2021·Obstetrics & Gynecology
DOI 10.1097/aog.0000000000004432PMC PMC10896115
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Abstract

PRAMS observational analysis of prenatal e-cigarette use and adverse birth outcomes.

Integrity signals

Registry

Crossref · 10.1097/aog.0000000000004432

Cites

36 of 36 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

19 of 27 cited sources checked · 2 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    The perception that e-cigarettes are less harmful than combustible cigarettes may contribute to their appeal among pregnant persons who have difficulty quitting smoking.

    “The perception that e-cigarettes are less harmful than combustible cigarette smoking may contribute to their appeal among pregnant persons who have difficulty quitting smoking.7,8”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [7] source

      The Introduction discusses smokers who cannot or will not quit, and the Discussion reports lower toxicant exposure among exclusive e-cigarette users than cigarette smokers. Neither section addresses pregnant persons’ perceptions of harm or whether those perceptions make e-cigarettes appealing; searches for those points found no passage in our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [8] source

      The paper’s “Hidden Formaldehyde in E-Cigarette Aerosols” section reports formaldehyde exposure from vaping and compares estimated risks with smoking. Searches for pregnancy, perceived harm, appeal, and difficulty quitting found no passage addressing why pregnant persons might choose e-cigarettes. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • Premisecitation

    Recent studies in mice have shown that chronic prenatal exposure to e-cigarettes containing nicotine resulted in decreased pup weight, body fat, and crown-rump length.

    “Recent studies in mice have shown that chronic prenatal exposure to e-cigarettes containing nicotine resulted in decreased pup weight, body fat, and crown-rump length, a measure of fetal growth and a marker of decreased uterine and fetal umbilical blood flow.14”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [14] source

      The Clinical Care and Public Health Recommendations advise pregnant women not to use e-cigarettes, but do not report mouse studies or fetal-growth outcomes. Searches for prenatal mouse exposure, pup weight, body fat, crown-rump length, and uterine or umbilical blood flow found no passage addressing the claim in our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • Premisecitation

    Reductions in pup weight, body fat, and crown-rump length were not observed for nicotine-free e-cigarettes.

    “One of these studies showed that these reductions were not observed for nicotine-free e-cigarettes.13”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [13] source

      The paper’s patient-characteristics table compares nicotine- and THC-containing product use among people with vaping-associated lung injury, and its Discussion advises pregnant women not to vape. Neither section reports an experiment involving pups or measurements of pup weight, body fat, or crown-rump length. Searches for those outcomes and for prenatal exposure found no passage addressing the claim. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
  • Premisecitation

    Exposure to e-cigarettes results in measurable exposure to nicotine metabolites and total nicotine equivalents.

    “Exposure to e-cigarettes has been shown to result in measurable exposure to nicotine metabolites and total nicotine equivalents.10”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [10] source

      The exposure-methods section (p. 6) reports measurable plasma cotinine, a nicotine metabolite, in offspring of mice exposed to nicotine-containing e-vapor. It does not report total nicotine equivalents; a search for that term found no such measurement in our copy. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • Findingown data

    Among 2016-2018 PRAMS respondents, the prevalence of e-cigarette use in the 3 months before pregnancy was 2.7% (95% CI 2.6-2.9%).

    “In the 3 months before pregnancy, 2.7% (95% CI 2.6–2.9%) of respondents used e-cigarettes”
    • Also stated in: § RESULTS · plain
      “2.7% (95% CI 2.6–2.9%) reported using e-cigarettes in the 3 months before pregnancy (but not during the last 3 months of pregnancy)”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 13
  • May combine two claims. 12

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    E-cigarette use has been increasing in the United States.

    “Electronic cigarette (e-cigarette) use, sometimes referred to as “electronic nicotine delivery systems,” has been increasing in the United States,5”
    Quote in the paperNot a substantial claim1 of 1 sources checked

  • May combine two claims.

    Premisecitation

    Recent animal studies have found that offspring from mothers exposed to e-cigarettes have short-term memory deficits, reduced anxiety, hyperactivity, increased global DNA methylation in the brain, impaired lung development, reduced crown-rump length and fetal weight, and increased oxidative stress and inflammation.

    “Recent animal studies have found that offspring from mothers exposed to e-cigarettes have short-term memory deficits, reduced anxiety, hyperactivity, increases in global DNA methylation in the brain,12 impaired lung development,13 reduced crown-rump length and fetal weight,14 and increased oxidative stress and inflammation.13,15”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [12] source
    • cites [13] source

      Split into 2 atoms — 0 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 2 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [14] source

      Split into 2 atoms — 0 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 2 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Previous animal studies have demonstrated harmful effects of chronic exposure to e-cigarette vapor, suggesting a biologically plausible relationship between e-cigarette exposure and adverse birth outcomes.

    “Previous animal studies have similarly demonstrated harmful effects of chronic exposure to e-cigarette vapor, suggesting a biologically plausible relationship between exposure to e-cigarettes and adverse birth outcomes.”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [14] source

      The Clinical Care and Public Health Recommendations section advises pregnant women not to use vaping products, but does not discuss animal studies or adverse birth outcomes. Searches for chronic vapor exposure, animal studies, and pregnancy or fetal outcomes found no passage in our copy supporting the attributed claim. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [13] source

      The Discussion advises pregnant women not to use vaping products, but it does not report animal studies, chronic vapor exposure, or adverse birth outcomes. Searches for those terms and for fetal or offspring outcomes found no supporting passage in our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Cigarette smoking is an important preventable cause of adverse pregnancy and neonatal outcomes including fetal growth restriction, preterm delivery, LBW, orofacial clefts, and SIDS.

    “Cigarette smoking remains an important preventable cause of adverse pregnancy and neonatal outcomes including fetal growth restriction, preterm delivery, low birth weight (LBW), orofacial clefts, and sudden infant death syndrome.1”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [1] source

      The “Pregnant Women and Fetuses” section attributes a proportion of preterm births and SIDS deaths to maternal smoking and discusses effects on birth weight. Our copy does not establish the claimed links to fetal growth restriction, low birth weight specifically, or orofacial clefts, so the full list is not supported. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    E-cigarettes are marketed as a less harmful alternative to cigarettes and as a smoking cessation aid for nonpregnant smokers.

    “these products are marketed as a less harmful alternative to cigarettes and a smoking cessation aid for nonpregnant smokers.6”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [6] source

      The Introduction (page not provided) says e-cigarettes were marketed in South Korea as an alternative to conventional cigarettes. It does not say they were marketed as less harmful or as a smoking-cessation aid, or specify nonpregnant smokers. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Adverse health effects in humans have been documented, linking e-cigarette use with increased risk of lung injury.

    “Adverse health effects in humans have also been documented, linking e-cigarette use with increased risk of lung injury.16–19”
    Quote in the paperNot a substantial claim1 of 4 sources checked
    • cites [16] source

      The opening section reports 215 possible cases of severe pulmonary disease associated with e-cigarette-product use, supporting the claim that lung injury in users had been documented. But the report says the definitive cause remained uncertain and does not establish an increased risk of lung injury from e-cigarette use generally. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [17] source
    • cites [18] source
    • cites [19] source

  • May combine two claims.

    Premisecitation

    Nicotine is considered a developmental toxicant and can have adverse fetal health consequences, including adverse brain development and increased risk of preterm delivery, stillbirth, and SIDS.

    “nicotine is considered a developmental toxicant and can have adverse health consequences for the fetus, including adverse consequences on brain development and increased risk of preterm delivery, stillbirth, and sudden infant death syndrome.2–4”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [2] source

      The Abstract (page unavailable) identifies e-cigarette use among pregnant women as a public health challenge, but it does not discuss nicotine as a developmental toxicant or specify fetal outcomes. Searches for developmental toxicity, brain development, preterm delivery, stillbirth, and sudden infant death syndrome found no passage addressing those claims in our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [3] source
    • cites [4] source

      The Introduction (page not provided) calls nicotine a reproductive toxicant and says it adversely affects pregnancy outcomes and fetal brain development. It associates preterm delivery with smoking during pregnancy, not specifically nicotine, and does not mention stillbirth or sudden infant death syndrome. (LLM, conf=0.89)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    E-cigarette products often contain nicotine, flavorings, and additives, and consumers may be exposed to other potential reproductive toxicants such as formaldehyde.

    “e-cigarette products often contain nicotine, flavorings and additives and consumers may be exposed to other potential reproductive toxicants included in e-cigarette products (ie, formaldehyde).9–11”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [9] source

      The Discussion (p. 8) says e-liquids contain flavourings, varying concentrations of nicotine, propylene glycol, and vegetable glycerin, supporting the general description of product contents. It also discusses potentially hazardous chemicals in e-liquids, but does not identify formaldehyde or describe it as a reproductive toxicant. A search for “formaldehyde” found no passage establishing that part of the claim. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [10] source

      The Introduction (p. 5) describes e-cigarette liquids as containing flavourings, solvents, and sometimes nicotine. The Discussion (p. 10) says heating solvents can produce toxic by-products and that exposure to nicotine-free vapour harmed mouse offspring. Our copy does not identify formaldehyde as one of those by-products or establish consumer exposure to it. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [11] source

  • May combine two claims.

    Premisecitation

    Nicotine crosses the placenta and binds to nicotinic acetylcholine receptors in the fetal nervous system, affecting neurodevelopment.

    “Nicotine is a developmental toxicant, which crosses the placenta and binds to nicotine acetyl choline receptors in the fetal nervous system, affecting neurodevelopment.2”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [2] source

      The Abstract identifies e-cigarette use among pregnant women as a public health concern, while the Methods and Results address trends in adult e-cigarette use. Searches for placental transfer, fetal nicotinic acetylcholine receptors, and neurodevelopment found no passage in our copy addressing the claimed mechanism. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    Overall, 0.7% of respondents were dual users and 0.3% were e-cigarette-only users during pregnancy.

    “Overall, 0.7% (95% CI 0.6–0.8%) of respondents were dual users and 0.3% (95% CI 0.2–0.4%) were e-cigarette–only users during pregnancy.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    There was no significant interaction between combustible cigarette smoking and e-cigarette use during pregnancy for SGA (P=.35) or LBW (P=.09).

    “but not for SGA (P=.35) or LBW (P=.09) (data not shown)”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    E-cigarette-only users more commonly reported daily use than dual users (61.5% vs 34.5%, P<.001).

    “Electronic cigarette–only users more commonly reported daily use of e-cigarettes compared with dual users (61.5% vs 34.5%, respectively; P<.001)”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Prenatal e-cigarette use does not further increase the risk of preterm birth in addition to combustible cigarette use during pregnancy.

    “it is possible that prenatal e-cigarette use does not further increase the risk of preterm birth in addition to combustible cigarette use during pregnancy.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The study proposal was reviewed and approved by the PRAMS Working Group.

    “Our study proposal was reviewed and approved by the PRAMS Working Group.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The PRAMS study protocol was approved by the institutional review boards of the CDC and each participating site.

    “The PRAMS study protocol has been approved by the institutional review boards of the CDC and each participating site.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning

    Linkage to birth certificate data allowed combining questionnaire data with medical information on birth weight and gestational age, enabling evaluation of medically recorded birth outcomes and minimizing missing data.

    “Linkage to birth certificate data allowed the opportunity to combine questionnaire data with medical information related to the birth (eg, birth weight and gestational age), enabling the evaluation of medically recorded birth outcomes and minimizing missing data.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductcitation

    Because PRAMS samples adults with a recent live birth, stillbirth and other pregnancy outcomes are not included, and the results are not representative of pregnancies not ending in a live birth.

    “Fourth, because PRAMS samples adults with a recent live birth, those who experience stillbirth or other pregnancy outcomes are not included,20 and these results are not representative of pregnancies not ending in a live birth.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [20]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Classified as probably not a substantial claim.

    Study design and conductown data

    The final adjusted model controlled for maternal age, race-ethnicity, maternal education, WIC use, adequacy of prenatal care, multivitamin use, and combustible cigarette use during pregnancy.

    “The final adjusted model compared e-cigarette use before and during pregnancy to nonuse, and controlled for maternal age, race–ethnicity, maternal education, use of WIC services during pregnancy, adequacy of prenatal care, multivitamin use, and combustible cigarette use during pregnancy.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    Adjustment variables were selected based on the minimum adjustment set identified from a directed acyclic graph.

    “Adjustment variables were selected for inclusion in the adjusted model based on the minimum adjustment set identified from a directed acyclic graph (Appendix 4, available online at http://links.lww.com/AOG/C338).”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    PRAMS data are weighted to account for sampling, nonresponse, and noncoverage.

    “PRAMS data are weighted to account for sampling, nonresponse, and noncoverage,20”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [20]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Study design and conductown data

    The unweighted number of e-cigarette users was not large (n=906), reducing precision of some effect estimates and the ability to detect small differences in pregnancy outcome prevalence.

    “Third, the unweighted number of e-cigarette users was not large (n5906) and consideration by categories of combustible cigarette smoking reduced the precision of some of our effect estimates and our ability to detect small difference in the prevalence of pregnancy outcomes.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    The analysis included data from 38 PRAMS sites that achieved a weighted response rate of 55% or higher for at least 1 year from 2016 to 2018.

    “We included data from 38 PRAMS sites (37 states and New York City) that achieved a weighted response rate of 55% or higher for at least 1 year from 2016 to 2018.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Inhaled nicotine reduces uterine artery blood flow and induces fluctuations in systemic blood pressure, which may reduce uteroplacental blood flow and result in adverse fetal effects such as fetal growth restriction.

    “Inhaled nicotine has been shown to reduce uterine artery blood flow and induce fluctuations in systemic blood pressure,30 which may reduce uteroplacental blood flow and resulting in adverse fetal effects such as fetal growth restriction.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [30] source
23 of 23

  • The paper relies on this without support.

    Few studies have examined whether e-cigarette use is associated with adverse birth outcomes among pregnant individuals.

    “Despite this, very few studies have assessed the potential association between e-cigarette use and adverse birth outcomes among pregnant individuals.”
1 of 1

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • One of these studies reported a significantly higher preterm birth prevalence for 'daily' exclusive-vapers than for a group combining exclusive-smokers and non-users, but not for non-daily vapers.

    “Additionally, one of these studies reported a significantly higher PTB prevalence for ‘daily’ exclusive-vapers than for a group combining exclusive-smokers and non-users, but not for non-daily vapers [49].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [49]

    The Results report significantly higher preterm-birth prevalence for daily e-cigarette users who did not smoke combustible cigarettes, but not for those who vaped less than daily. The comparison was with e-cigarette nonusers within the nonsmoker group, not a group combining exclusive smokers and nonusers. No page number is available in our copy. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • One study found that the prevalence of preterm births was similar for dual-users and 'non-vapers' (combination of exclusive-smokers and non-users), irrespective of the frequency of vaping.

    “One of the latter studies also found that the prevalence of preterm births was similar for dual-users and ‘non-vapers’ (combination of exclusive-smokers and non-users), irrespective of the frequency of vaping [49].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [49]

    The Results (page not provided) report no difference in preterm-birth prevalence between dual users and e-cigarette nonusers who smoked combustible cigarettes, for either daily or less-than-daily vaping. The paper does not report that frequency-specific comparison against the claimed combined group of exclusive smokers and people who used neither product. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • One study reported that, compared with a group combining exclusive-smokers and non-users, prevalence of SGA for exclusive-vapers was similar, irrespective of whether vaping was daily or less than daily.

    “Additionally, one study reported that, compared with a group combining exclusive-smokers and non-users, prevalence of SGA for exclusive-vapers was similar, irrespective of whether vaping was daily or less than daily [49].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [49]

    The Results (page not available) report no significant difference in SGA prevalence for prenatal e-cigarette users overall, and the Discussion says the study did not identify an association with SGA. But the frequency-specific Results explicitly report no SGA difference for dual users, not exclusive vapers, and the study compared groups within smoking strata rather than against a group combining exclusive smokers and non-users. (LLM, conf=0.84)

    Experimental — accuracy not yet measured

  • In 17 studies it was not assessed whether any of those counted as vaping used non-nicotine vapes.

    “and in 17 studies it was not assessed whether any of those counted as vaping used non-nicotine vapes [32, 35, 36, 38, 42, 43, 45, 46, 48–56].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [49]

  • Two studies observed significantly greater preterm birth rates for exclusive-vapers than for non-users.

    “Conversely, two studies observed significantly greater PTB rates for exclusive-vapers than for non-users [43, 49].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [49]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Less-than-daily use is also associated with low birth weight

    Major

    The abstract says associations appeared only for daily users, but the results report an increased prevalence of low birth weight among less-than-daily users, with a confidence interval above 1.

  • Prepregnancy-use percentage excludes some prepregnancy users

    Minor

    The abstract presents 2.7% as the percentage who used e-cigarettes before pregnancy. The results identify 2.7% as those who used them before pregnancy but not late in pregnancy, while also reporting that most late-pregnancy users had used them before pregnancy; the overall prepregnancy percentage must therefore be higher.

2 of 2

Cites

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2 of the 38 references couldn’t be matched to a known paper.

Cited by

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Related

Authors
Regan, A. K., Bombard, J. M., O’Hegarty, M. M., Smith, R. A., & Tong, V. T.
Affiliations
Centers for Disease Control and Prevention (US)
ORCID
Venue
Obstetrics & Gynecology
Publisher
Ovid Technologies (Wolters Kluwer Health)
Published
2021-06-09
Volume
138
Issue
1
Pages
85-94
ISSN
0029-7844 (ISSN-L)
DOI
10.1097/aog.0000000000004432
PMC
PMC10896115
OpenAlex
W3174146600
Cited by
74
References
38
Citations by year
2026: 10 · 2025: 10 · 2024: 22 · 2023: 14 · 2022: 16 · 2021: 2
FWCI
8.47
Type
journal article
Language
en
Open access
Locations
  • Obstetrics and Gynecology (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • National Institutes of Health (CC999999)
  • Centers for Disease Control and Prevention
Topics
  • Health Sciences › Medicine › Physiology › Smoking Behavior and Cessation
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Prenatal Substance Exposure Effects
  • Health Sciences › Health Professions › General Health Professions › Maternal and Neonatal Healthcare
Keywords
electronic cigarettes, adverse birth outcomes, low birth weight, preterm birth, small for gestational age, combustible cigarette smoking, prenatal tobacco exposure, PRAMS
MeSH terms
Vaping, Adolescent, Adult, Female, Humans, Infant, Low Birth Weight, Infant, Newborn, Infant, Small for Gestational Age, Pregnancy, Pregnancy Outcome, Surveys and Questionnaires, United States, Prevalence, Maternal Exposure, Premature Birth, Young Adult

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Claims read under definition version 3 (extract-v3) on 2026-09-28.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-09-28.

Cited sources are checked by gpt-6-sol.

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