{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T15:53:02Z","timestamp":1793893982188,"version":"4.8.0"},"reference-count":35,"publisher":"Public Library of Science (PLoS)","issue":"11","license":[{"start":{"date-parts":[[2024,11,26]],"date-time":"2024-11-26T00:00:00Z","timestamp":1732579200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000272","name":"NIHR","doi-asserted-by":"crossref","award":["16\/167\/123"],"award-info":[{"award-number":["16\/167\/123"]}],"id":[{"id":"10.13039\/501100000272","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["www.plosmedicine.org"],"crossmark-restriction":false},"short-container-title":["PLoS Med"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>Chronic or gestational hypertension complicates approximately 7% of pregnancies, half of which reach 37 weeks\u2019 gestation. Early term birth (at 37 to 38 weeks) may reduce maternal complications, cesareans, stillbirths, and costs but may increase neonatal morbidity. In the WILL Trial (When to Induce Labour to Limit risk in pregnancy hypertension), we aimed to establish optimal timing of birth for women with chronic or gestational hypertension who reach term and remain well.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods and findings<\/jats:title>\n<jats:p>This 50-centre, open-label, randomised trial in the United Kingdom included an economic analysis. WILL randomised women with chronic or gestational hypertension at 36 to 37 weeks and a singleton fetus, and who provided documented informed consent to \u201cPlanned early term birth at 38<jats:sup>+0\u20133<\/jats:sup> weeks\u201d (intervention) or \u201cusual care at term\u201d (control). The coprimary outcomes were \u201cpoor maternal outcome\u201d (composite of severe hypertension, maternal death, or maternal morbidity; superiority hypothesis) and \u201cneonatal care unit admission for \u22654 hours\u201d (noninferiority hypothesis). The key secondary was cesarean. Follow-up was to 6 weeks postpartum. The planned sample size was 540\/group. Analysis was by intention-to-treat. A total of 403 participants (37.3% of target) were randomised to the intervention (<jats:italic>n<\/jats:italic> = 201) or control group (<jats:italic>n<\/jats:italic> = 202), from 3 June 2019 to 19 December 2022, when the funder stopped the trial for delayed recruitment. In the intervention (versus control) group, losses to follow-up were 18\/201 (9%) versus 15\/202 (7%). In each group, maternal age was about 30 years, about one-fifth of women were from ethnic minorities, over half had obesity, approximately half had chronic hypertension, and most were on antihypertensives with normal blood pressure. In the intervention (versus control) group, birth was a median of 0.9 weeks earlier (38.4 [38.3 to 38.6] versus 39.3 [38.7 to 39.9] weeks). There was no evidence of a difference in \u201cpoor maternal outcome\u201d (27\/201 [13%] versus 24\/202 [12%], respectively; adjusted risk ratio [aRR] 1.16, 95% confidence interval [CI] 0.72 to 1.87). For \u201cneonatal care unit admission for \u22654 hours,\u201d the intervention was considered noninferior to the control as the adjusted risk difference (aRD) 95% CI upper bound did not cross the 8% prespecified noninferiority margin (14\/201 [7%] versus 14\/202 [7%], respectively; aRD 0.003, 95% CI \u22120.05 to +0.06), although event rates were lower-than-estimated. The intervention (versus control) was associated with no difference in cesarean (58\/201 [29%] versus 72\/202 [36%], respectively; aRR 0.81, 95% CI 0.61 to 1.08. There were no serious adverse events. Limitations include our smaller-than-planned sample size, and lower-than-anticipated event rates, so the findings may not be generalisable to where hypertension is not treated with antihypertensive therapy.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>In this study, we observed that most women with chronic or gestational hypertension required labour induction, and planned birth at 38<jats:sup>+0\u20133<\/jats:sup> weeks (versus usual care) resulted in birth an average of 6 days earlier, and no differences in poor maternal outcome or neonatal morbidity. Our findings provide reassurance about planned birth at 38<jats:sup>+0\u20133<\/jats:sup> weeks as a clinical option for these women.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Trial registration<\/jats:title>\n<jats:p>isrctn.com <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/www.isrctn.com\/ISRCTN77258279\" xlink:type=\"simple\">ISRCTN77258279<\/jats:ext-link>.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pmed.1004481","type":"journal-article","created":{"date-parts":[[2024,11,26]],"date-time":"2024-11-26T18:53:36Z","timestamp":1732647216000},"page":"e1004481","update-policy":"https:\/\/doi.org\/10.1371\/journal.pmed.corrections_policy","source":"Crossref","is-referenced-by-count":20,"title":["Determining optimal timing of birth for women with chronic or gestational hypertension at term: The WILL (When to Induce Labour to Limit risk in pregnancy hypertension) randomised trial"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1355-610X","authenticated-orcid":true,"given":"Laura A.","family":"Magee","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5727-6049","authenticated-orcid":true,"given":"Katie","family":"Kirkham","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sue","family":"Tohill","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8083-2947","authenticated-orcid":true,"given":"Eleni","family":"Gkini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0473-0532","authenticated-orcid":true,"given":"Catherine A.","family":"Moakes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1691-3221","authenticated-orcid":true,"given":"Jon","family":"Dorling","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4561-8256","authenticated-orcid":true,"given":"Marcus","family":"Green","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6618-6018","authenticated-orcid":true,"given":"Jennifer A.","family":"Hutcheon","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mishal","family":"Javed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7608-4923","authenticated-orcid":true,"given":"Jesse","family":"Kigozi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8337-550X","authenticated-orcid":true,"given":"Ben W. M.","family":"Mol","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joel","family":"Singer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2937-8368","authenticated-orcid":true,"given":"Pollyanna","family":"Hardy","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2690-6583","authenticated-orcid":true,"given":"Clive","family":"Stubbs","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9764-6876","authenticated-orcid":true,"given":"James G.","family":"Thornton","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4136-3070","authenticated-orcid":true,"given":"Peter","family":"von Dadelszen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"the WILL Trial Study Group","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,11,26]]},"reference":[{"key":"pmed.1004481.ref001","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.preghy.2021.09.008","article-title":"The 2021 International Society for the Study of Hypertension in Pregnancy classification, diagnosis & management recommendations for international practice","volume":"27","author":"LA Magee","year":"2022","journal-title":"Pregnancy Hypertens"},{"issue":"5","key":"pmed.1004481.ref002","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1056\/NEJMoa1404595","article-title":"Less-tight versus tight control of hypertension in pregnancy","volume":"372","author":"LA Magee","year":"2015","journal-title":"N Engl J Med"},{"issue":"1","key":"pmed.1004481.ref003","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1111\/j.1471-0528.2010.02754.x","article-title":"Optimal timing of delivery in pregnancies with pre-existing hypertension","volume":"118","author":"JA Hutcheon","year":"2011","journal-title":"BJOG"},{"issue":"3","key":"pmed.1004481.ref004","doi-asserted-by":"crossref","first-page":"214 e1","DOI":"10.1016\/j.ajog.2012.06.009","article-title":"What is the optimal time for delivery in women with gestational hypertension?","volume":"207","author":"MO Cruz","year":"2012","journal-title":"Am J Obstet Gynecol"},{"issue":"3","key":"pmed.1004481.ref005","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1097\/AOG.0000000000002800","article-title":"Timing of Delivery in Women With Chronic Hypertension","volume":"132","author":"M Ram","year":"2018","journal-title":"Obstet Gynecol"},{"issue":"6","key":"pmed.1004481.ref006","doi-asserted-by":"crossref","first-page":"1101","DOI":"10.1097\/AOG.0000000000001435","article-title":"Gestational Age of Delivery in Pregnancies Complicated by Chronic Hypertension","volume":"127","author":"LM Harper","year":"2016","journal-title":"Obstet Gynecol"},{"issue":"13","key":"pmed.1004481.ref007","doi-asserted-by":"crossref","first-page":"1577","DOI":"10.1111\/j.1471-0528.2010.02710.x","article-title":"An economic analysis of induction of labour and expectant monitoring in women with gestational hypertension or pre-eclampsia at term (HYPITAT trial)","volume":"117","author":"SM Vijgen","year":"2010","journal-title":"BJOG"},{"issue":"4","key":"pmed.1004481.ref008","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1016\/j.clp.2013.07.004","article-title":"Respiratory disorders in moderately preterm, late preterm, and early term infants","volume":"40","author":"AD Mahoney","year":"2013","journal-title":"Clin Perinatol"},{"issue":"4","key":"pmed.1004481.ref009","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1002\/uog.20224","article-title":"Delivery or expectant management for prevention of adverse maternal and neonatal outcomes in hypertensive disorders of pregnancy: an individual participant data meta-analysis","volume":"53","author":"TP Bernardes","year":"2019","journal-title":"Ultrasound Obstet Gynecol"},{"issue":"9694","key":"pmed.1004481.ref010","doi-asserted-by":"crossref","first-page":"979","DOI":"10.1016\/S0140-6736(09)60736-4","article-title":"Induction of labour versus expectant monitoring for gestational hypertension or mild pre-eclampsia after 36 weeks\u2019 gestation (HYPITAT): a multicentre, open-label randomised controlled trial","volume":"374","author":"CM Koopmans","year":"2009","journal-title":"Lancet"},{"key":"pmed.1004481.ref011","unstructured":"Hypertension in pregnancy: diagnosis and management. 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