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Cited by 7Neuroscience of respiration and sleepPrenatal Substance Exposure EffectsAutopsy Techniques and Outcomes

Harmful Effect of Intrauterine Smoke Exposure on Neuronal Control of “Fetal Breathing System” in Stillbirths

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Lavezzi, Anna M., Pusiol, Teresa, Paradiso, Beatrice·2022·International Journal of Environmental Research and Public Health
DOI 10.3390/ijerph19074164PMC PMC8999022
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Abstract

This article is aimed to contribute to the current knowledge on the role of toxic substances such as nicotine on sudden intrauterine unexplained deaths’ (SIUDS’) pathogenetic mechanisms. The in-depth histopathological examination of the autonomic nervous system in wide groups of victims of SIUDS (47 cases) and controls (20 cases), with both smoking and no-smoking mothers, highlighted the frequent presence of the hypodevelopment of brainstem structures checking the vital functions. In particular, the hypoplasia of the pontine parafacial nucleus together with hypoplastic lungs for gestational age were observed in SIUDS cases with mothers who smoked cigarettes, including electronic ones. The results allow us to assume that the products of cigarette smoke during pregnancy can easily cross the placental barrier, thus entering the fetal circulation and damaging the most sensitive organs, such as lungs and brain. In a non-negligible percentage of SIUDS, the mothers did not smoke. Furthermore, based on previous and ongoing studies conducted through analytical procedures and the use of scanning electron microscopy, the authors envisage the involvement of toxic nanoparticles (such as agricultural pesticides and nanomaterials increasingly used in biomedicine, bioscience and biotechnology) in the death pathogenesis, with similar mechanisms to those of nicotine.

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  • One study reported that, among cases of sudden intrauterine unexplained deaths, adverse neuropathological brainstem outcomes (pulmonary hypoplasia, pFn hypoplasia) were more common for infants of exclusive-vapers.

    “The second reported that, among cases of sudden intrauterine unexplained deaths, adverse neuropathological brainstem outcomes (pulmonary hypoplasia, pFn hypoplasia) were more common for infants of exclusive-vapers [44], although neither samples sizes nor statistical tests were reported.”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [44]

    Results §3.3 reports five mothers who used e-cigarettes, separately from four who used both e-cigarettes and traditional cigarettes, among SIUDS cases with pulmonary hypoplasia. The Discussion says all nine e-cigarette-exposed cases had both lung and pFn hypodevelopment, supporting the finding for exclusive vapers. The paper does not report a separate statistical comparison showing these outcomes were more common among exclusive vapers; contrary to the citing sentence’s qualification, it does report their sample size. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • One study observed that adverse neuropathological brainstem outcomes were more common for infants exposed to dual-use compared with infants of non-users.

    “One study observed that adverse neuropathological brainstem outcomes were more common for infants who were exposed to dual-use compared with infants of non-users and were similar among infants exposed to exclusive-smoking, dual-use or exclusive-vaping [44].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [44]

    Results §3.3 reports four mothers who used both e-cigarettes and traditional cigarettes among the SIUDS cases with pulmonary hypoplasia; Discussion §4 says all nine e-cigarette-exposed cases had hypodevelopment of the parafacial nucleus and lungs. Results §3.4 reports a strong correlation between maternal smoking and brainstem findings, but the paper does not give a direct dual-use-versus-non-user comparison of neuropathological outcomes. Its cases were stillbirths, rather than infants generally. (LLM, conf=0.85)

    Experimental — accuracy not yet measured

  • Adverse neuropathological brainstem outcomes were similar among infants exposed to exclusive-smoking, dual-use or exclusive-vaping.

    “One study observed that adverse neuropathological brainstem outcomes were more common for infants who were exposed to dual-use compared with infants of non-users and were similar among infants exposed to exclusive-smoking, dual-use or exclusive-vaping [44].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [44]

    The Results (§3.3; page unavailable) identify five mothers who used e-cigarettes and four who used both e-cigarettes and traditional cigarettes. The Discussion (§4; page unavailable) reports hypodevelopment of the parafacial nucleus and lungs in all nine cases and describes the same defects in cases with smoking mothers. It does not directly compare neuropathological outcomes across the three exclusive-smoking, dual-use and exclusive-vaping groups, and its cases were stillbirths rather than live-born infants. (LLM, conf=0.83)

    Experimental — accuracy not yet measured

  • All three studies reported similar levels of adverse neurological outcomes for exclusive-vaping and exclusive-smoking for reflex, motor maturity and self-regulation scores, relative frequency of mouth movements, and neuropathological brainstem outcomes.

    “All three studies reported similar levels of adverse neurological outcomes for exclusive-vaping and exclusive-smoking, for the following outcomes: reflex, motor maturity and self-regulation scores [40], relative frequency of mouth movements [41], and neuropathological brainstem outcomes [44].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [44]

    The Results (§3.3) identify five mothers who used e-cigarettes and four who used both e-cigarettes and traditional cigarettes. The Discussion (§4) reports hypodevelopment of the parafacial nucleus and lungs in all nine cases, but does not compare the frequency or severity of brainstem findings between exclusive vaping and exclusive smoking. The reflex, motor-maturity, self-regulation, and mouth-movement outcomes are attached to other citations in the citing sentence, not this source. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Among three small studies of neurological outcomes, for at least one outcome, two reported higher risk for exclusive-vaping compared with non-use.

    “In summary, among three small studies of neurological outcomes, for at least one outcome, two reported exclusive-vaping having a similar risk to non-use [40, 41] and two reported higher risk for exclusive-vaping [40, 44].”

    From Vaping during pregnancy: a systematic review of health outcomes. (2024) · cites this paper as [44]

    The Results (§3.3; page unavailable) identify five mothers who used e-cigarettes without reported conventional-cigarette use among the stillbirth cases with pulmonary hypoplasia. The Discussion (§4; page unavailable) says the nine e-cigarette-exposed cases had underdevelopment of a respiratory neuronal center, but the paper does not report a neurological-outcome risk comparison between exclusive vaping and non-use. (LLM, conf=0.82)

    Experimental — accuracy not yet measured

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Authors
Lavezzi, A. M., Pusiol, T., & Paradiso, B.
Affiliations
  • University of Milan (IT)
  • Institute of Anatomic Pathology, APSS, 38122 Trento, Italy
Corresponding author
Lavezzi, Anna M.
ORCID
Venue
International Journal of Environmental Research and Public Health
Publisher
MDPI AG
Published
2022-03-31
Volume
19
Issue
7
Pages
4164
ISSN
1660-4601 (ISSN-L)
DOI
10.3390/ijerph19074164
PMC
PMC8999022
OpenAlex
W4221127477
Cited by
7
References
66
Citations by year
2026: 1 · 2025: 1 · 2024: 4 · 2023: 1
FWCI
0.79
Type
journal article
Language
en
Open access
Licence
Locations
  • International Journal of Environmental Research and Public Health (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Topics
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Neuroscience of respiration and sleep
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Prenatal Substance Exposure Effects
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Autopsy Techniques and Outcomes
Keywords
stillbirth, maternal smoking, nicotine, autonomic nervous system, brainstem hypoplasia, fetal lung hypoplasia, placental barrier, electronic cigarettes, nanoparticle toxicity, pesticide toxicity
MeSH terms
Female, Fetal Death, Humans, Nicotine, Placenta, Pregnancy, Sudden Infant Death, Stillbirth

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