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We analyzed the effects of maternal age at first cesarean on adverse outcomes of pregnancy in the second cesarean using multivariate logistic regression analysis.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The study consisted of 10,206 singleton pregnancies. Women were at first cesarean between 18 and 24, 25\u201329, 30\u201334, and\u2009\u2265\u200935\u2009years of age; and numbered 2711, 5524, 1751, and 220 cases, respectively. Maternal age between 18 and 24\u2009years at first cesarean increased the risk of placenta accreta spectrum (aOR, 1.499; 95% CI, 1.12\u20132.01), placenta previa (aOR, 1.349; 95% CI, 1.07\u20131.70), intrahepatic cholestasis of pregnancy (aOR, 1.947; 95% CI, 1.24\u20133.07), postpartum hemorrhage (aOR, 1.505; 95% CI, 1.05\u20132.16), and blood transfusion (aOR, 1.517; 95% CI, 1.21\u20131.91) in the second cesarean compared with the reference group (aged 25\u201329\u2009years). In addition, maternal age\u2009\u2265\u200935\u2009years at first cesarean was a risk factor for premature rupture of membranes (aOR, 1.556; 95% CI, 1.08\u20132.24), placental abruption (aOR, 6.464, 95% CI, 1.33\u201331.51), uterine rupture (aOR, 7.952; 95% CI, 1.43\u201344.10), puerperal infection (aOR, 6.864; 95% CI, 1.95\u201324.22), neonatal mild asphyxia (aOR, 4.339; 95% CI, 1.53\u201312.32), severe asphyxia (aOR, 18.439; 95% CI, 1.54\u2013220.95), and admission to a neonatal intensive care unit (aOR, 2.825; 95% CI, 1.54\u20135.17) compared with the reference group (aged 25\u201329\u2009years).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>Maternal age between 18 and 24\u2009years or advanced maternal age at first cesarean was an independent risk factor for adverse maternal outcomes with the second cesarean. Advanced maternal age at the first cesarean specifically increased adverse neonatal outcomes with the second. Therefore, decisions as to whether to perform a first cesarean at a young or advanced maternal age must be critically evaluated.<\/jats:p><\/jats:sec>","DOI":"10.1186\/s12884-021-03608-9","type":"journal-article","created":{"date-parts":[[2021,2,12]],"date-time":"2021-02-12T20:35:32Z","timestamp":1613162132000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Maternal age at first cesarean delivery related to adverse pregnancy outcomes in a second cesarean delivery: a multicenter, historical, cross-sectional cohort study"],"prefix":"10.1186","volume":"21","author":[{"given":"Shilei","family":"Bi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lizi","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingsi","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minshan","family":"Huang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijun","family":"Huang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shanshan","family":"Zeng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yulian","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingyu","family":"Liang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinping","family":"Jia","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suiwen","family":"Wen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yinli","family":"Cao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaoshuai","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoyan","family":"Xu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ling","family":"Feng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianlan","family":"Zhao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yangyu","family":"Zhao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiying","family":"Zhu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongbo","family":"Qi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lanzhen","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongtian","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2156-0835","authenticated-orcid":false,"given":"Zhijian","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lili","family":"Du","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dunjin","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,2,12]]},"reference":[{"issue":"5","key":"3608_CR1","doi-asserted-by":"publisher","first-page":"338","DOI":"10.1053\/j.semperi.2015.06.006","volume":"39","author":"W Brown","year":"2015","unstructured":"Brown W, Ahmed S, Roche N, Sonneveldt E, Darmstadt GL. 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All of the methods were performed in accordance with the relevant guidelines and regulations, and the statements on consent for participation were signed by participants and their legally authorized representatives.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no conflict of interest.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"126"}}