{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T02:54:07Z","timestamp":1788144847711,"version":"build-2803163510"},"reference-count":28,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2024,1,2]],"date-time":"2024-01-02T00:00:00Z","timestamp":1704153600000},"content-version":"vor","delay-in-days":1,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Ultrasound in Obstet &amp;amp; Gyne"],"published-print":{"date-parts":[[2024,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title><jats:sec><jats:title>Objective<\/jats:title><jats:p>Low\u2010dose aspirin (LDA) has been shown to reduce the risk of preterm pre\u2010eclampsia and it has been suggested that it should be recommended for all pregnancies. However, some studies have reported an association between LDA and an increased risk of bleeding complications in pregnancy. Our aim was to evaluate the risk of placental abruption and postpartum hemorrhage (PPH) in patients for whom their healthcare provider had recommended prophylactic aspirin.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>This multicenter cohort study included 72\u2009598 singleton births at 19 hospitals in the USA, between January 2019 and December 2021. Pregnancies complicated by placenta previa\/accreta, birth occurring at less than 24\u2009weeks' gestation, multiple pregnancy or those with data missing for aspirin recommendation were excluded. Propensity scores were calculated using 20 features spanning sociodemographic factors, medical history, year and hospital providing care. The association between LDA recommendation and placental abruption or PPH was estimated by inverse\u2010probability treatment weighting using the propensity scores.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>We included 71\u2009627 pregnancies in the final analysis. Aspirin was recommended to 6677 (9.3%) and was more likely to be recommended for pregnant individuals who were 35\u2009years or older (<jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001), had a body mass index of 30\u2009kg\/m<jats:sup>2<\/jats:sup> or higher (<jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001), had prepregnancy hypertension (<jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001) and who had a Cesarean delivery (<jats:italic>P<\/jats:italic>\u2009&lt;\u20090.001). Overall, 1.7% of the study cohort (1205 pregnancies) developed preterm pre\u2010eclampsia: 1.3% in the no\u2010aspirin and 5.8% in the aspirin group. After inverse\u2010probability weighting with propensity scores, aspirin was associated with increased risk of placental abruption (adjusted odds ratio (aOR), 1.44 (95%\u2009CI, 1.04\u20132.00)) and PPH (aOR, 1.21 (95%\u2009CI, 1.05\u20131.39)). The aOR translated to a number needed to harm with LDA of 79 (95%\u2009CI, 43\u2013330) for PPH and 287 (95%\u2009CI, 127\u20133151) for placental abruption.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>LDA recommendation in pregnancy was associated with increased risk for placental abruption and for PPH. Our results support the need for more research into aspirin use and bleeding complications in pregnancy before recommending it beyond the highest\u2010risk pregnancies. \u00a9 2023 The Authors. <jats:italic>Ultrasound in Obstetrics &amp; Gynecology<\/jats:italic> published by John Wiley &amp; Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.<\/jats:p><\/jats:sec>","DOI":"10.1002\/uog.27472","type":"journal-article","created":{"date-parts":[[2023,9,7]],"date-time":"2023-09-07T06:55:38Z","timestamp":1694069738000},"page":"81-87","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Propensity score analysis of low\u2010dose aspirin and bleeding complications in pregnancy"],"prefix":"10.1002","volume":"63","author":[{"given":"V.","family":"Souter","sequence":"first","affiliation":[{"name":"Foundation for Health Care Quality  Seattle WA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"I.","family":"Painter","sequence":"additional","affiliation":[{"name":"Foundation for Health Care Quality  Seattle WA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"K.","family":"Sitcov","sequence":"additional","affiliation":[{"name":"Foundation for Health Care Quality  Seattle WA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2802-7670","authenticated-orcid":false,"given":"A.","family":"Khalil","sequence":"additional","affiliation":[{"name":"Fetal Medicine Unit St George's University Hospitals NHS Foundation Trust, University of London  London UK"},{"name":"Vascular Biology Research Centre, Molecular and Clinical Sciences Research Institute St George's University of London  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2024,1,2]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa1704559"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/ijgo.12802"},{"key":"e_1_2_8_4_1","unstructured":"National Institute for Health and Care Excellence(2019).Hypertension in pregnancy: diagnosis and management. NICE guideline [NG 133].www.nice.org.uk\/guidance\/ng133."},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.7326\/M14-1884"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2021.14781"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2021.42343"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000003167"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000003413"},{"key":"e_1_2_8_10_1","article-title":"Antiplatelet agents for preventing pre\u2010eclampsia and its complications","volume":"2019","author":"Duley L","year":"2019","journal-title":"Cochrane Database Syst Rev"},{"issue":"95","key":"e_1_2_8_11_1","first-page":"e1","article-title":"Aspirin use during pregnancy and the risk of bleeding complications: a Swedish population\u2010based cohort study","volume":"224","author":"Hastie R","year":"2021","journal-title":"Am J Obstet Gynecol"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.1136\/bmjopen-2018-022056"},{"key":"e_1_2_8_13_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000001294"},{"key":"e_1_2_8_14_1","unstructured":"Economic Innovation Group Distressed Communities Index.https:\/\/eig.org\/distressed\u2010communities\/."},{"key":"e_1_2_8_15_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000002708"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1097\/AOG.0000000000000322"},{"key":"e_1_2_8_17_1","first-page":"e168","article-title":"183. Postpartum hemorrhage. American College of Obstetricians and Gynecologists","volume":"130","author":"ACOG Practice Bulletin No","year":"2017","journal-title":"Obstet Gynecol"},{"key":"e_1_2_8_18_1","volume-title":"R: A language and environment for statistical computing","author":"R Core Team","year":"2020"},{"key":"e_1_2_8_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2017.11.561"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2020.08.045"},{"key":"e_1_2_8_21_1","doi-asserted-by":"publisher","DOI":"10.3389\/fmed.2023.1111371"},{"key":"e_1_2_8_22_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.preghy.2021.09.008"},{"key":"e_1_2_8_23_1","unstructured":"The World Health Organization.WHO recommendations on antiplatelet agents for the prevention of pre\u2010eclampsia.2021.https:\/\/www.who.int\/publications\/i\/item\/9789240037540."},{"issue":"685","key":"e_1_2_8_24_1","first-page":"e1","article-title":"Aspirin for Evidence\u2010Based Preeclampsia Prevention trial: influence of compliance on beneficial effect of aspirin in prevention of preterm preeclampsia","volume":"217","author":"Wright D","year":"2017","journal-title":"Am J Obstet Gynecol"},{"key":"e_1_2_8_25_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2017.12.238"},{"key":"e_1_2_8_26_1","doi-asserted-by":"publisher","DOI":"10.1002\/uog.20859"},{"key":"e_1_2_8_27_1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2021.8551"},{"issue":"251","key":"e_1_2_8_28_1","first-page":"e1","article-title":"A randomized controlled trial of low\u2010dose aspirin for the prevention of preeclampsia in women at high risk in China","volume":"226","author":"Lin L","year":"2022","journal-title":"Am J Obstet Gynecol"},{"key":"e_1_2_8_29_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2023.04.039"}],"container-title":["Ultrasound in Obstetrics &amp; Gynecology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/uog.27472","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,4,2]],"date-time":"2024-04-02T06:05:59Z","timestamp":1712037959000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1002\/uog.27472"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,1]]},"references-count":28,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2024,1]]}},"alternative-id":["10.1002\/uog.27472"],"URL":"https:\/\/doi.org\/10.1002\/uog.27472","archive":["Portico"],"relation":{},"ISSN":["0960-7692","1469-0705"],"issn-type":[{"value":"0960-7692","type":"print"},{"value":"1469-0705","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,1]]},"assertion":[{"value":"2023-05-17","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2023-08-22","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2024-01-02","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}