{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T01:46:11Z","timestamp":1782783971003,"version":"3.54.5"},"reference-count":30,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T00:00:00Z","timestamp":1782691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Short interdelivery interval (IDI) is associated with adverse perinatal outcomes, but its relationship with objective neonatal acid\u2013base markers, postpartum anemia, and early postnatal depression remains poorly characterized. We examined IDI &lt; 24 months across four pre-specified outcome domains: neonatal acid\u2013base status, maternal composite morbidity, postpartum anemia, and early postnatal depression. Methods: This single-center retrospective cohort study included 851 women with two consecutive singleton live births at Ankara Etlik City Hospital between 2023 and 2025. Women were classified by IDI as short (&lt;24 months; n = 635) or standard (\u226524 months; n = 216). Multivariable logistic regression provided the primary inference. Sensitivity analyses included inverse probability of treatment weighting (IPTW), restricted cubic splines (4 df), within-mother paired analysis, multiple imputation by chained equations (MICE \u00d7 20), Firth penalization, E-values, and Benjamini\u2013Hochberg false discovery rate (FDR) correction across 13 outcomes. Results: After FDR correction, short IDI was associated with postpartum anemia (adjusted odds ratio [aOR] 1.84, 95% confidence interval (CI) 1.26\u20132.68; q = 0.022) and with an Edinburgh Postnatal Depression Scale score \u226513 (aOR 1.93, 95% CI 1.20\u20133.10; q = 0.042); umbilical-artery pH &lt; 7.10 did not cross the FDR threshold (aOR 2.37, 1.17\u20134.82; q = 0.075) and is reported as an exploratory, hypothesis-generating signal. Postpartum anemia did not mediate the IDI\u2013depression association (proportion mediated 0.6%, 95% CI \u221213.1% to +13.5%). Conclusions: Short IDI was associated with maternal hematologic and psychosocial signals; the IDI\u2013depression link appears non-hematologic. Neonatal acid\u2013base findings did not meet the FDR threshold and are exploratory. Multicenter validation is warranted.<\/jats:p>","DOI":"10.3390\/jcm15135053","type":"journal-article","created":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T00:55:11Z","timestamp":1782780911000},"page":"5053","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Short Interdelivery Interval and Neonatal Acid\u2013Base Status, Postpartum Anemia, and Postnatal Depression: A Retrospective Cohort Study with Within-Mother Sensitivity Analysis"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9861-6767","authenticated-orcid":false,"given":"\u00d6mer Osman","family":"Ero\u011flu","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ankara Etlik City Hospital, Varl\u0131k Mahallesi, Halil Sezai Erkut Caddesi, Yenimahalle, 06170 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-5049-1415","authenticated-orcid":false,"given":"Cans\u0131n","family":"Ero\u011flu","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ankara Etlik City Hospital, Varl\u0131k Mahallesi, Halil Sezai Erkut Caddesi, Yenimahalle, 06170 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-1950-9041","authenticated-orcid":false,"given":"Sait","family":"Erbey","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ankara Etlik City Hospital, Varl\u0131k Mahallesi, Halil Sezai Erkut Caddesi, Yenimahalle, 06170 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3812-3455","authenticated-orcid":false,"given":"Mehmet Alican","family":"Sapmaz","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ankara Etlik City Hospital, Varl\u0131k Mahallesi, Halil Sezai Erkut Caddesi, Yenimahalle, 06170 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-2964-729X","authenticated-orcid":false,"given":"Murat","family":"Polat","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ankara Etlik City Hospital, Varl\u0131k Mahallesi, Halil Sezai Erkut Caddesi, Yenimahalle, 06170 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4381-6099","authenticated-orcid":false,"given":"\u00c7a\u011fanay","family":"Soysal","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Ankara Etlik City Hospital, Varl\u0131k Mahallesi, Halil Sezai Erkut Caddesi, Yenimahalle, 06170 Ankara, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1809","DOI":"10.1001\/jama.295.15.1809","article-title":"Birth spacing and risk of adverse perinatal outcomes: A meta-analysis","volume":"295","year":"2006","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1056\/NEJM199902253400801","article-title":"Effect of the interval between pregnancies on perinatal outcomes","volume":"340","author":"Zhu","year":"1999","journal-title":"N. 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