{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T06:30:43Z","timestamp":1787725843077,"version":"build-2784847793"},"reference-count":37,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T00:00:00Z","timestamp":1787702400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pediatr."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To evaluate the association between the COVID-19 pandemic and preterm birth (PTB) rates, stratified by gestational age, in a low-infection pregnant population delivering at a non-designated COVID-19 maternity center.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>A hospital-based retrospective cohort study was conducted, comparing deliveries during the pandemic period (January 2020\u2013April 2022) with the pre-pandemic period (January 2017\u2013April 2019). Logistic regression models were used to assess crude and adjusted associations, with singleton-only sensitivity analyses performed to address confounding by multiple gestation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 67,238 deliveries were included, comprising 29,310 pandemic and 37,928 pre-pandemic births. Overall PTB rates were similar between the two periods (7.5% vs. 7.4%; adjusted odds ratio [AOR]\u2009=\u20091.0, 95% confidence interval [CI]: 1.0\u20131.1,\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u20090.66). Preterm birth excluding extremely preterm birth (EPTB) (28\n                      <jats:sup>+0<\/jats:sup>\n                      \u201336\u207a\n                      <jats:sup>6<\/jats:sup>\n                      weeks) rates also remained stable (7.3% vs. 7.3%; AOR\u2009=\u20091.0, 95% CI: 0.9\u20131.1,\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u20090.95). In contrast, the rate of EPTB (22\n                      <jats:sup>+0<\/jats:sup>\n                      \u201327\u207a\n                      <jats:sup>6<\/jats:sup>\n                      weeks) was significantly higher during the pandemic (0.2% vs. 0.1%), with a nearly threefold increased risk after adjustment (AOR\u2009=\u20092.8, 95%CI: 1.7\u20134.7,\n                      <jats:italic>P<\/jats:italic>\n                      \u2009&amp;lt;\u20090.001). This association persisted in the singleton-only cohort (AOR\u2009=\u20093.2, 95% CI: 1.8\u20135.9,\n                      <jats:italic>P<\/jats:italic>\n                      \u2009&amp;lt;\u20090.001), despite the rarity of this outcome.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Among this low-infection cohort reflecting pandemic measures rather than viral effects, overall and preterm birth excluding EPTB rates remained stable during the pandemic, though a significant increase in extremely preterm birth (&amp;lt;28 weeks) risk was noted, indicating a subtype-specific effect requiring further validation.<\/jats:p>\n                  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