{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T21:14:44Z","timestamp":1793222084696,"version":"4.5.0"},"update-to":[{"DOI":"10.1371\/journal.pmed.1003611","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2021,5,11]],"date-time":"2021-05-11T00:00:00Z","timestamp":1620691200000}}],"reference-count":30,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T00:00:00Z","timestamp":1619481600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000865","name":"Bill and Melinda Gates Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000865","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013373","name":"NIHR Oxford Biomedical Research Centre","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100013373","id-type":"DOI","asserted-by":"publisher"}]}],"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>Gestational hypertensive and acute hypotensive disorders are associated with maternal morbidity and mortality worldwide. However, physiological blood pressure changes in pregnancy are insufficiently defined. We describe blood pressure changes across healthy pregnancies from the International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st) Fetal Growth Longitudinal Study (FGLS) to produce international, gestational age-specific, smoothed centiles (third, 10th, 50th, 90th, and 97th) for blood pressure.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods and findings<\/jats:title>\n<jats:p>Secondary analysis of a prospective, longitudinal, observational cohort study (2009 to 2016) was conducted across 8 diverse urban areas in Brazil, China, India, Italy, Kenya, Oman, the United Kingdom, and the United States of America. We enrolled healthy women at low risk of pregnancy complications. We measured blood pressure using standardised methodology and validated equipment at enrolment at &lt;14 weeks, then every 5 \u00b1 1 weeks until delivery.<\/jats:p>\n<jats:p>We enrolled 4,607 (35%) women of 13,108 screened. The mean maternal age was 28\u00b74 (standard deviation [SD] 3.9) years; 97% (4,204\/4,321) of women were married or living with a partner, and 68% (2,955\/4,321) were nulliparous. Their mean body mass index (BMI) was 23.3 (SD 3.0) kg\/m<jats:sup>2<\/jats:sup>. Systolic blood pressure was lowest at 12 weeks: Median was 111.5 (95% CI 111.3 to 111.8) mmHg, rising to a median maximum of 119.6 (95% CI 118.9 to 120.3) mmHg at 40 weeks\u2019 gestation, a difference of 8.1 (95% CI 7.4 to 8.8) mmHg. Median diastolic blood pressure decreased from 12 weeks: 69.1 (95% CI 68.9 to 69.3) mmHg to a minimum of 68.5 (95% CI 68.3 to 68.7) mmHg at 19<jats:sup>+5<\/jats:sup> weeks\u2019 gestation, a change of \u22120\u00b76 (95% CI \u22120.8 to \u22120.4) mmHg. Diastolic blood pressure subsequently increased to a maximum of 76.3 (95% CI 75.9 to 76.8) mmHg at 40 weeks\u2019 gestation. Systolic blood pressure fell by &gt;14 mmHg or diastolic blood pressure by &gt;11 mmHg in fewer than 10% of women at any gestational age. Fewer than 10% of women increased their systolic blood pressure by &gt;24 mmHg or diastolic blood pressure by &gt;18 mmHg at any gestational age. The study\u2019s main limitations were the unavailability of prepregnancy blood pressure values and inability to explore circadian effects because time of day was not recorded for the blood pressure measurements.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Our findings provide international, gestational age-specific centiles and limits of acceptable change to facilitate earlier recognition of deteriorating health in pregnant women. These centiles challenge the idea of a clinically significant midpregnancy drop in blood pressure.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pmed.1003611","type":"journal-article","created":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T19:56:11Z","timestamp":1619553371000},"page":"e1003611","update-policy":"https:\/\/doi.org\/10.1371\/journal.pmed.corrections_policy","source":"Crossref","is-referenced-by-count":21,"title":["International gestational age-specific centiles for blood pressure in pregnancy from the INTERGROWTH-21st Project in 8 countries: A longitudinal cohort study"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0230-2662","authenticated-orcid":true,"given":"Lauren J.","family":"Green","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0135-9317","authenticated-orcid":true,"given":"Stephen H.","family":"Kennedy","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1927-1594","authenticated-orcid":true,"given":"Lucy","family":"Mackillop","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4654-7311","authenticated-orcid":true,"given":"Stephen","family":"Gerry","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manorama","family":"Purwar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleonora","family":"Staines Urias","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leila","family":"Cheikh Ismail","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernando","family":"Barros","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2465-2180","authenticated-orcid":true,"given":"Cesar","family":"Victora","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2371-890X","authenticated-orcid":true,"given":"Maria","family":"Carvalho","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3116-2593","authenticated-orcid":true,"given":"Eric","family":"Ohuma","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yasmin","family":"Jaffer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3060-3772","authenticated-orcid":true,"given":"J. Alison","family":"Noble","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Gravett","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruyan","family":"Pang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ann","family":"Lambert","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Enrico","family":"Bertino","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aris T.","family":"Papageorghiou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1970-1141","authenticated-orcid":true,"given":"Cutberto","family":"Garza","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0637-599X","authenticated-orcid":true,"given":"Zulfiqar","family":"Bhutta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9","family":"Villar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1023-3927","authenticated-orcid":true,"given":"Peter","family":"Watkinson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"for the International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st)","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2021,4,27]]},"reference":[{"key":"pmed.1003611.ref001","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1161\/HYPERTENSIONAHA.117.10803","article-title":"Hypertensive disorders of pregnancy: ISSHP classification, diagnosis, and management recommendations for international practice","volume":"72","author":"MA Brown","year":"2018","journal-title":"Hypertension"},{"key":"pmed.1003611.ref002","doi-asserted-by":"crossref","first-page":"2011","DOI":"10.1371\/journal.pmed.1001672","article-title":"Severe Maternal Sepsis in the UK, 2011\u20132012: A National Case-Control Study","volume":"11","author":"CD Acosta","year":"2014","journal-title":"PLoS Med"},{"key":"pmed.1003611.ref003","doi-asserted-by":"crossref","first-page":"299ra122","DOI":"10.1126\/scitranslmed.aab3719","article-title":"A targeted real-time early warning score (TREWScore) for septic shock","volume":"7","author":"KE Henry","year":"2015","journal-title":"Sci Transl Med"},{"key":"pmed.1003611.ref004","doi-asserted-by":"crossref","first-page":"383","DOI":"10.1111\/1471-0528.15286","article-title":"The DiPEP study: an observational study of the diagnostic accuracy of clinical assessment, D-dimer and chest x-ray for suspected pulmonary embolism in pregnancy and postpartum","volume":"126","author":"S Goodacre","year":"2019","journal-title":"BJOG"},{"key":"pmed.1003611.ref005","author":"M Knight","year":"2019","journal-title":"Saving Lives, Improving Mothers\u2019 Care. 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