{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,9]],"date-time":"2026-11-09T07:16:22Z","timestamp":1794208582998,"version":"4.8.0"},"reference-count":25,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,5,25]],"date-time":"2021-05-25T00:00:00Z","timestamp":1621900800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,5,25]],"date-time":"2021-05-25T00:00:00Z","timestamp":1621900800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Med"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>Post-term gestation beyond 41<jats:sup>+6<\/jats:sup> completed weeks of gestation is known to be associated with a sharp increase in the risk of stillbirth and perinatal mortality. However, the risk of common adverse outcomes related to labour, such as shoulder dystocia and post-partum haemorrhage for those delivering at this advanced gestation, remains poorly characterised. The objective of this study was to examine the risk of adverse, labour-related outcomes for women progressing to 42 weeks gestation or beyond, compared with those giving birth at 39 completed weeks.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>We performed a state-wide cohort study using routinely collected perinatal data in Australia. Comparing the two gestation cohorts, we examined the adjusted relative risk of clinically significant labour-related adverse outcomes, including macrosomia (\u2265 4500 at birth), post-partum haemorrhage (\u22651000 ml), shoulder dystocia, 3rd or 4th degree perineal tear and unplanned caesarean section. Parity, maternal age and mode of birth were adjusted for using logistic regression.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>The study cohort included 91,314 women who birthed at 39 completed weeks and 4317 at \u226542 completed weeks. Compared to 39 weeks gestation, those giving birth \u226542 weeks gestation had an adjusted relative risk (aRR) of 1.85 (95% CI 1.55\u20132.20) for post-partum haemorrhage following vaginal birth, 2.29 (95% CI 1.89\u20132.78) following instrumental birth and 1.44 (95% CI 1.17\u20131.78) following emergency caesarean section; 1.43 (95% CI 1.16\u20131.77) for shoulder dystocia (for non-macrosomic babies); and 1.22 (95% CI 1.03\u20131.45) for 3rd or 4th degree perineal tear (all women). The adjusted relative risk of giving birth to a macrosomic baby was 10.19 (95% CI 8.26\u201312.57) among nulliparous women and 4.71 (95% CI 3.90\u20135.68) among multiparous women. The risk of unplanned caesarean section was 1.96 (95% CI 1.86\u20132.06) following any labour and 1.47 (95% CI 1.38\u20131.56) following induction of labour.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Giving birth at \u226542 weeks gestation may be an under-recognised risk factor for several important, labour-related adverse outcomes. Clinicians should be aware that labour at this advanced gestation incurs a higher risk of adverse outcomes. In addition to known perinatal risks, the risk of obstetric complications should be considered in the counselling of women labouring at post-term gestation.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12916-021-01988-5","type":"journal-article","created":{"date-parts":[[2021,5,25]],"date-time":"2021-05-25T01:02:36Z","timestamp":1621904556000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Risk of major labour-related complications for pregnancies progressing to 42 weeks or beyond"],"prefix":"10.1186","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8662-5188","authenticated-orcid":false,"given":"Anthea C.","family":"Lindquist","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roxanne M.","family":"Hastie","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard J.","family":"Hiscock","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natasha L.","family":"Pritchard","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan P.","family":"Walker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Tong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,5,25]]},"reference":[{"issue":"3","key":"1988_CR1","first-page":"175","volume":"4","author":"M Galal","year":"2012","unstructured":"Galal M, Symonds I, Murray H, Petraglia F, Smith R. 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This project used de-identified, routinely collected health data, and as such, obtaining individual participant consent was not considered to be necessary by the ethical review board.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"126"}}