{
  "abstract": "Background: Low birthweight (LBW) remains a major global public health challenge, with long-term consequences for neonatal survival and chronic disease risk. Maternal exposure to ambient ozone (O3) has been implicated in fetal growth restriction, but evidence remains inconsistent. Methods: We conducted a retrospective cohort study of 14,381 term singleton live births in Zhejiang Province, East China, during the COVID-19 lockdown and quarantine period. Maternal O3 exposure during each trimester and the entire pregnancy was estimated using data from nearest atmospheric monitoring stations, with refined time-activity patterns accounting for home and workplace locations. Results: In multivariable linear regression adjusted for the pre-specified covariates, maternal O3 exposure averaged over the entire pregnancy was inversely associated with birthweight (pooled estimate across sex- and residence-stratified models: β = −2.1 g per μg/m3, 95% CI: −3.6 to −0.5; stratum-specific β ranged from −2.24 to −0.92). An interquartile range (IQR) of approximately 10–15 μg/m3 in entire-pregnancy O3 exposure increase was associated with an estimated birthweight reduction of about 20–33 g; the range reflected the combination of stratum-specific β estimates and stratum-specific IQRs. The explained variance was small as indicated by R2, showing that O3 was not a powerful individual-level predictor of birthweight; the precisely estimated β nonetheless reflected a systematic shift in the population distribution of birthweight. Conclusions: Maternal O3 exposure during pregnancy was associated with reduced birthweight in a sex- and window-specific manner. The third trimester was more stronger association period for female fetuses, whereas cumulative exposure across mid-to-whole pregnancy was more critical for males. Maternal nutritional intake is a plausible modifiable factor that may attenuate susceptibility, but the present study did not measure diet, food insecurity, or psychological stress. Future studies should incorporate dietary assessment and biomarkers to test this hypothesis.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China",
    "Zhejiang Key Laboratory of Precise Protection and Promotion of Fertility, Hangzhou 310016, China",
    "Zhejiang Provincial Clinical Research Center for Reproductive Health and Disease, Hangzhou 310016, China",
    "The First Clinical Medical Institute, Wenzhou Medical University, Wenzhou 325035, China",
    "School of Computer Science and Technology, Hangzhou Dianzi University, Hangzhou 310018, China",
    "School of Public Health, Zhejiang University School of Medicine, Hangzhou 310058, China",
    "Department of Nursing, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China",
    "Hangzhou Environmental Monitoring Center Station, Hangzhou 310007, China",
    "School of engineering, Hangzhou Normal University, Hangzhou 311121, China"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0,
        1,
        2
      ],
      "name": "Cuiyu Yang",
      "orcid": "0009-0005-6466-437X"
    },
    {
      "affs": [
        3
      ],
      "name": "Tu Hong"
    },
    {
      "affs": [
        4
      ],
      "name": "Jiamin Xu"
    },
    {
      "affs": [
        5
      ],
      "name": "Xinhui Wang",
      "orcid": "0000-0001-7713-6262"
    },
    {
      "affs": [
        6
      ],
      "name": "Lixia Bi"
    },
    {
      "affs": [
        7
      ],
      "name": "Jiandong Shen"
    },
    {
      "affs": [
        8
      ],
      "name": "Rui Feng",
      "orcid": "0000-0002-2384-819X"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/da3q2vk0r1emp.bib",
  "cited_by": 0,
  "doi": "10.3390/nu18223762",
  "fulltext_url": null,
  "id": "da3q2vk0r1emp",
  "issns": [
    "2072-6643"
  ],
  "landing_url": "https://www.mdpi.com/2072-6643/18/22/3762",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-12",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/da3q2vk0r1emp.ris",
  "sources": [
    {
      "first_seen": "2026-11-13T00:21:25Z",
      "native_id": "10.3390/nu18223762",
      "source": "crossref",
      "url": "https://www.mdpi.com/2072-6643/18/22/3762"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "issn:2072-6643",
      "subfield": "nutrition"
    }
  ],
  "title": "Maternal Exposure to Ambient Ozone and Birthweight Reduction During COVID-19 Epidemic in East China: A Sex- and Window-Specific Retrospective Cohort Study",
  "title_text": "Maternal Exposure to Ambient Ozone and Birthweight Reduction During COVID-19 Epidemic in East China: A Sex- and Window-Specific Retrospective Cohort Study",
  "type": "peer-reviewed",
  "updated_at": "2026-11-14T00:21:05Z",
  "url": "https://research.draconitic.com/paper/da3q2vk0r1emp",
  "venue": "Nutrients",
  "versions": []
}