{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T08:02:39Z","timestamp":1784707359098,"version":"3.55.0"},"reference-count":21,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T00:00:00Z","timestamp":1784678400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T00:00:00Z","timestamp":1784678400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Intl J Gynecology &amp; Obste"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Retained placenta (RP) is an obstetric complication associated with postpartum hemorrhage, sepsis, and maternal morbidity. While maternal body mass index (BMI) influences pregnancy outcomes, its associations with RP are unclear. We aimed to examine associations between BMI, demographic and clinical factors, and RP using a nationally representative inpatient dataset.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      This retrospective study analyzed data of women aged \u226518\u2009years with delivery hospitalizations from the US Nationwide Inpatient Sample 2016\u20132020. RP was identified using the ICD\u201010 codes. Included women were classified on the basis of BMI as non\u2010obese (&lt;30.0\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ), obese (30.0\u201339.9\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ), and morbidly obese (\u226540.0\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ). Weighted logistic regression analysis determined associations between study variables and RP occurrence.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 3\u2009590\u2009940 delivery hospitalizations, 28\u2009935 women (0.8%) had RP. Multivariable analysis identified advanced maternal age (adjusted odds ratio [aOR]\u2009=\u20091.046, 95% CI: 1.044\u20131.049), obesity (aOR\u2009=\u20091.18), morbid obesity (aOR\u2009=\u20091.25), polycystic ovary syndrome (PCOS) (aOR\u2009=\u20091.33), endometriosis (aOR\u2009=\u20092.28), smoking (aOR\u2009=\u20091.33), multiple pregnancy (aOR\u2009=\u20092.37), uterine surgery (aOR\u2009=\u20092.04), abortion (aOR\u2009=\u20091.43), and infertility (aOR\u2009=\u20091.87) as independent risk factors for RP. Cesarean delivery (vs. vaginal delivery) was significantly associated with a lower risk of RP (aOR\u2009=\u20090.14). Subgroup analyses confirmed consistent risk factors across age, prematurity, and PPROM, with multiple pregnancy, endometriosis, PCOS, obesity, and smoking remaining significant predictors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Obesity is an independent risk factor for RP, and morbid obesity confers the highest risk. Study findings emphasize the need for patient\u2010focused obstetric management in high\u2010risk populations.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/ijgo.71214","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T07:29:37Z","timestamp":1784705377000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Associations between body mass index and retained placenta in delivery hospitalizations: Analysis of the Nationwide Inpatient Sample, 2016\u20132020"],"prefix":"10.1002","author":[{"given":"Jui\u2010Der","family":"Liou","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology Shin Kong Wu Ho\u2010Su Memorial Hospital  Taipei City Taiwan"},{"name":"Director of Cytogenetic Laboratory, Department of Obstetrics and Gynecology Shin Kong Wu Ho\u2010Su Memorial Hospital  Taipei City 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