{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T07:46:48Z","timestamp":1785829608701,"version":"3.56.0"},"reference-count":25,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/100010269","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["223601"],"award-info":[{"award-number":["223601"]}],"id":[{"id":"10.13039\/100010269","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100014338","name":"National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care Yorkshire and Humber","doi-asserted-by":"publisher","award":["NIHR200166"],"award-info":[{"award-number":["NIHR200166"]}],"id":[{"id":"10.13039\/501100014338","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000664","name":"Health Technology Assessment Programme","doi-asserted-by":"publisher","award":["16\/150\/06"],"award-info":[{"award-number":["16\/150\/06"]}],"id":[{"id":"10.13039\/501100000664","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Paediatric Perinatal Epid"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Clinical guidelines now recommend administering intrapartum antibiotic prophylaxis (IAP) before skin incision at caesarean section to prevent maternal infection. However, this practice exposes the fetus to antibiotics, raising concerns about potential long\u2010term effects on the infant microbiome and the risk of childhood obesity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To assess whether the timing of IAP at caesarean section\u2014before skin incision versus after umbilical cord clamping\u2014is associated with childhood obesity at age 4\u20135\u2009years.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We conducted a quasi\u2010experimental study of a hospital\u2010wide policy change in clinical practice using data from two birth cohorts (Born in Bradford [BiB] and Born in Bradford's Better Start [BiBBS]). The study included 1985 children of White British or Pakistani heritage born by caesarean section between 2007 and 2019. Children exposed to pre\u2010incision IAP (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u2009324) were compared with those unexposed (post\u2010cord clamping IAP;\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20091661). The primary outcome was obesity (BMI z\u2010score &gt;\u200995th percentile) at age 4\u20135\u2009years. Adjusted Risk Ratios (aRR) were estimated using multivariable Poisson regression stratified by ethnicity.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The prevalence of obesity was 11.9%. Adjusted risk ratios for obesity were 1.25 (95% CI 0.53 to 2.98) for White British children and 1.25 (95% CI 0.64 to 2.43) for Pakistani children. Similarly, estimates for BMI z\u2010score had wide confidence intervals indicating, limited precision.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>We did not observe a clear difference in childhood obesity at 4\u20135\u2009years between pre\u2010incision and post\u2010cord clamping prophylactic antibiotics at caesarean section. Confidence intervals were wide, and modest clinically relevant effects cannot be excluded. Findings are compatible with no large adverse effect and may provide reassurance regarding the metabolic safety of current clinical practice.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/ppe.70179","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T07:01:22Z","timestamp":1785826882000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Effect of Intrapartum Antibiotic Prophylaxis at Caesarean Section on Childhood Obesity: A Quasi\u2010Experimental Study in Two Bi\u2010Ethnic\n                    <scp>UK<\/scp>\n                    Cohorts"],"prefix":"10.1111","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0427-1783","authenticated-orcid":false,"given":"Gillian","family":"Santorelli","sequence":"first","affiliation":[{"name":"Bradford Institute for Health Research Bradford Teaching Hospitals NHS Foundation Trust  Bradford UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0455-7469","authenticated-orcid":false,"given":"Lucy","family":"Pembrey","sequence":"additional","affiliation":[{"name":"Department of Medical Statistics London School of Hygiene &amp; Tropical Medicine  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4926-3827","authenticated-orcid":false,"given":"Sergio Souza","family":"da Cunha","sequence":"additional","affiliation":[{"name":"Bradford Institute for Health Research Bradford Teaching Hospitals NHS Foundation Trust  Bradford UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6778-8128","authenticated-orcid":false,"given":"Emily S.","family":"Petherick","sequence":"additional","affiliation":[{"name":"School of Sport, Exercise and Health Sciences Loughborough University  Loughborough UK"},{"name":"National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester  Leicester UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2579-1999","authenticated-orcid":false,"given":"Ellena","family":"Badrick","sequence":"additional","affiliation":[{"name":"Bradford Institute for Health Research Bradford Teaching Hospitals NHS Foundation Trust  Bradford UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-1119-4060","authenticated-orcid":false,"given":"Lila","family":"Goodwin","sequence":"additional","affiliation":[{"name":"Department of Medical Statistics London School of Hygiene &amp; Tropical Medicine  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8701-4912","authenticated-orcid":false,"given":"Sam","family":"Oddie","sequence":"additional","affiliation":[{"name":"Bradford Institute for Health Research Bradford Teaching Hospitals NHS Foundation Trust  Bradford UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-7852","authenticated-orcid":false,"given":"Neil","family":"Pearce","sequence":"additional","affiliation":[{"name":"Department of Medical Statistics London School of Hygiene &amp; Tropical Medicine  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9572-7293","authenticated-orcid":false,"given":"John","family":"Wright","sequence":"additional","affiliation":[{"name":"Bradford Institute for Health Research Bradford Teaching Hospitals NHS Foundation Trust  Bradford UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,8,4]]},"reference":[{"key":"e_1_2_12_2_1","unstructured":"NHS Digital \u201cNHS Maternity Statistics England \u201dhttps:\/\/digital.nhs.uk\/data\u2010and\u2010information\/publications\/statistical\/nhs\u2010maternity\u2010statistics."},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/14651858.CD007482.pub3"},{"key":"e_1_2_12_4_1","unstructured":"NICE \u201cCaesarean Section: Clinical Guideline CG132 \u201d(2011)."},{"key":"e_1_2_12_5_1","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1038\/ijo.2014.180","article-title":"Prenatal Exposure to Antibiotics, Cesarean Section and Risk of Childhood Obesity","volume":"39","author":"Mueller N. 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