{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T07:57:53Z","timestamp":1790668673901,"version":"4.1.0"},"reference-count":23,"publisher":"Wiley","issue":"6","license":[{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"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":["Pregnancy"],"published-print":{"date-parts":[[2026,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Placenta previa (PP) is a well\u2010recognized obstetric complication with established maternal risks, particularly hemorrhage, that contribute significantly to maternal morbidity. In contrast, low\u2010lying placenta (LLP) has historically been grouped with previa in both coding and clinical practice, limiting our ability to study its imparted associated outcomes as a distinct entity. However, in 2017, coding revisions allowed for a parsed diagnosis of LLP and PP and enabled the current study of differentiated associated outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objective(s)<\/jats:title>\n                    <jats:p>To describe and compare the independent rates of hemorrhage and severe maternal morbidity (SMM) associated with LLP and PP relative to normal placentation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective analysis using the Nationwide Readmissions Database (NRD) from 2017 through 2019, reflecting the initial 3 years of coding for LLP. Patients with multifetal gestation, ectopic\/molar pregnancies, and other placental abnormalities were excluded. The primary outcome was hemorrhage, defined using international classification of diseases (ICD)\u201010 codes for ante\u2010, intra\u2010, and postpartum hemorrhage (PPH). SMM was defined using the Centers for Disease Control and Prevention's index, which includes a range of life\u2010threatening complications such as disseminated intravascular coagulation, hysterectomy, and shock. Baseline characteristics and maternal outcomes were compared using chi\u2010square tests for categorical variables and Kruskal\u2013Wallis tests for continuous variables. Multivariable regression analysis was used to evaluate the risk ratios (RRs) of adverse outcomes across these groups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Among 5,625,432 singleton deliveries, 11,486 were diagnosed with LLP and 21,356 with PP. Compared to normal placentation, LLP was associated with a significantly higher rate of hemorrhage (21.1%\u00a0vs. 4.0%,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001), SMM (4.5%\u00a0vs. 1.8%,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001), maternal blood transfusion (3.3%\u00a0vs. 1.1%,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001), hysterectomy (0.2%\u00a0vs.\u00a0&lt;\u00a00.1%,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001), and hysterectomy within 30 days (0.2%\u00a0vs. 0.0%,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001). LLP was also associated with longer median hospital stay (3\u00a0vs. 2 days,\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001) and higher total charges ($21,410\u00a0vs. $17,024;\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001). In adjusted analyses using normal placentation as the referent group, LLP remained independently associated with hemorrhage (adjusted relative risk [aRR], 4.72; 95% CI, 4.56\u20134.89), SMM (aRR, 2.16; 95% confidence interval [CI], 1.99\u20132.35), and transfusion (aRR, 2.61; 95% CI, 2.36\u20132.88). PP was associated with even higher risks of hemorrhage (aRR, 8.93), SMM (aRR, 4.22), and transfusion (aRR, 5.69) compared to those with normal placentation (all\n                      <jats:italic>p<\/jats:italic>\n                      \u00a0&lt;\u00a00.001).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>With the institution of distinct coding for LLP in 2017, we were able to distinguish between patients with LLP and PP. While PP remains associated with the highest risk of poor maternal outcomes, patients with an antenatal diagnosis of LLP also have an increased risk of hemorrhage and SMM relative to those with normal placentation. These findings should be considered during the prenatal counseling and management of patients with LLP.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/pmf2.70468","type":"journal-article","created":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T07:38:57Z","timestamp":1790667537000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Low\u2010lying placenta is associated with increased risk of hemorrhage and severe maternal morbidity: A nationwide analysis"],"prefix":"10.1002","volume":"2","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2257-7519","authenticated-orcid":false,"given":"May","family":"Abiad","sequence":"first","affiliation":[{"name":"Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children's Hospital Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3044-238X","authenticated-orcid":false,"given":"Giulia","family":"Bonanni","sequence":"additional","affiliation":[{"name":"Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children's Hospital Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1415-2086","authenticated-orcid":false,"given":"Nikan","family":"Zargarzadeh","sequence":"additional","affiliation":[{"name":"Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children's Hospital Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4056-1585","authenticated-orcid":false,"given":"Ali","family":"Javinani","sequence":"additional","affiliation":[{"name":"Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children's Hospital Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6062-6772","authenticated-orcid":false,"given":"Scott A.","family":"Shainker","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6543-4078","authenticated-orcid":false,"given":"Anna M.","family":"Modest","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George R.","family":"Saade","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology Eastern Virginia Medical School  Norfolk Virginia USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2960-0371","authenticated-orcid":false,"given":"Kjersti","family":"Aagaard","sequence":"additional","affiliation":[{"name":"Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children's Hospital Harvard Medical School  Boston Massachusetts USA"},{"name":"HCA Healthcare and HCA Healthcare Research Institute  Nashville Tennessee USA"},{"name":"HCA Healthcare, Texas Maternal Fetal Medicine  Houston Texas USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6333-3177","authenticated-orcid":false,"given":"Alireza A.","family":"Shamshirsaz","sequence":"additional","affiliation":[{"name":"Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children's Hospital Harvard Medical School  Boston Massachusetts USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,29]]},"reference":[{"issue":"19","key":"e_1_2_8_2_1","doi-asserted-by":"crossref","first-page":"3221","DOI":"10.1080\/14767058.2019.1570118","article-title":"Diagnosis and Management of Placenta Previa and Low Placental Implantation","volume":"33","author":"Alouini S.","year":"2020","journal-title":"The Journal of Maternal\u2010Fetal & Neonatal Medicine"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1080\/14767058.2023.2204998"},{"issue":"6","key":"e_1_2_8_4_1","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1111\/tmi.12100","article-title":"Prevalence of Placenta Praevia by World Region: A Systematic Review and Meta\u2010Analysis","volume":"18","author":"Cresswell J. 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