{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T05:48:06Z","timestamp":1782452886035,"version":"3.54.5"},"reference-count":21,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"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: Shift work is a form of circadian dysregulation, which has been associated with adverse reproductive health outcomes. However, the association between circadian dysregulation and ovarian reserve remains uncertain. The present study examines whether shift work is associated with lower AMH levels in women seeking fertility treatment. Methods: This retrospective cohort study includes female patients aged 20\u201339 years presenting between February 2023 and June 2024. Patients were excluded if they had only one ovary, a current cancer diagnosis, or past chemotherapy use. Demographic and medical data were obtained from the electronic medical record. AMH levels were compared between daytime workers and shift workers. Results: A total of 1135 patients met inclusion criteria. The median age was 35 years (IQR 32\u201337). Of these, 89% (n = 1014) reported daytime work, and 11% (n = 121) reported shift work, comprising 102 working rotating shifts, seven working night shifts, and 12 working evening shifts. Daytime-only workers had a median AMH of 17.20 pmol\/L (9.1\u201330.0). Combined shift workers had a median AMH of 17.10 pmol\/L (8.1\u201331.0). There was no statistically significant difference in AMH levels between daytime workers and shift workers (p = 0.935). Although not significant, the odds of having low AMH levels (&lt;7 pmol\/L) were 25% higher among shift workers compared to daytime workers (OR 1.246, p = 0.345). Conclusions: In this cohort, AMH levels did not significantly differ between daytime and shift workers, offering reassurance to individuals required to engage in shift work. Future research should include larger cohorts and incorporate more comprehensive measures of circadian disruption.<\/jats:p>","DOI":"10.3390\/jcm15124769","type":"journal-article","created":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T13:04:04Z","timestamp":1781874244000},"page":"4769","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Shift Work as a Potential Risk Factor for Lower Ovarian Reserve: A Study of Fertility Patients"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6849-0059","authenticated-orcid":false,"given":"Adeolu","family":"Banjoko","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynaecology, Temerty Faculty of Medicine, University of Toronto, 1 King\u2019s College Circle, Medical Sciences Building Room 2109, Toronto, ON M5S 1A8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-3712-3328","authenticated-orcid":false,"given":"Nina","family":"Harris","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynaecology, Temerty Faculty of Medicine, University of Toronto, 1 King\u2019s College Circle, Medical Sciences Building Room 2109, Toronto, ON M5S 1A8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-9070-3634","authenticated-orcid":false,"given":"Sara","family":"Mousavi","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynaecology, Temerty Faculty of Medicine, University of Toronto, 1 King\u2019s College Circle, Medical Sciences Building Room 2109, Toronto, ON M5S 1A8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stella","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Biostatistics, University Health Network, Toronto, ON M5G 1X8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ella","family":"Huszti","sequence":"additional","affiliation":[{"name":"Department of Biostatistics, University Health Network, Toronto, ON M5G 1X8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zachary M.","family":"Ferraro","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynaecology, Temerty Faculty of Medicine, University of Toronto, 1 King\u2019s College Circle, Medical Sciences Building Room 2109, Toronto, ON M5S 1A8, Canada"},{"name":"Mount Sinai Fertility, Sinai Health System, 250 Dundas Street West Suite 700, Toronto, ON M7A 1G1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5108-0114","authenticated-orcid":false,"given":"Claire Ann","family":"Jones","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynaecology, Temerty Faculty of Medicine, University of Toronto, 1 King\u2019s College Circle, Medical Sciences Building Room 2109, Toronto, ON M5S 1A8, Canada"},{"name":"Mount Sinai Fertility, Sinai Health System, 250 Dundas Street West Suite 700, Toronto, ON M7A 1G1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sciarra, F., Franceschini, E., Campolo, F., Gianfrilli, D., Pallotti, F., Paoli, D., Isidori, A.M., and Venneri, M.A. (2020). Disruption of circadian rhythms: A crucial factor. Int. J. Mol. Sci., 21.","DOI":"10.3390\/ijms21113943"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"bqab117","DOI":"10.1210\/endocr\/bqab117","article-title":"Circadian rhythms within the female hpg axis: From physiology to etiology","volume":"162","author":"Shao","year":"2021","journal-title":"Endocrinology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1177\/07487304211064218","article-title":"Disturbance of the Circadian System in Shift Work and Its Health Impact","volume":"37","author":"Boivin","year":"2021","journal-title":"J. Biol. Rhythm."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"6049","DOI":"10.1210\/jc.2019-00803","article-title":"Endogenous Circadian Regulation of Female Reproductive Hormones","volume":"104","author":"Rahman","year":"2019","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1186\/s13048-018-0471-3","article-title":"Is the aging human ovary still ticking?: Expression of clock-genes in luteinized granulosa cells of young and older women","volume":"11","author":"Brzezinski","year":"2018","journal-title":"J. Ovarian Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"612","DOI":"10.1016\/j.fertnstert.2015.05.017","article-title":"Diminished Ovarian Reserve (DOR) in the US ART Population: Diagnostic Trends Among 181,536 Cycles from the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System (SART CORS) HHS Public Access Author manuscript","volume":"104","author":"Devine","year":"2015","journal-title":"Fertil. Steril."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"595943","DOI":"10.3389\/fpubh.2020.595943","article-title":"Night Shift Among Women: Is It Associated with Difficulty Conceiving a First Birth?","volume":"8","author":"Fernandez","year":"2020","journal-title":"Front. Public Health"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"715","DOI":"10.1016\/j.fertnstert.2020.08.1429","article-title":"Impact of sleep on female and male reproductive functions: A systematic review","volume":"115","author":"Caetano","year":"2021","journal-title":"Fertil. Steril."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"337","DOI":"10.1007\/s13224-020-01362-0","article-title":"AMH and Its Clinical Implications","volume":"70","author":"Shrikhande","year":"2020","journal-title":"J. Obstet. Gynecol. India"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Annalisa, R., Dominic, S., and Nikolaos, P. (2022). Editorial: Diminished Ovarian Reserve and Poor Ovarian Response: Diagnostic and Therapeutic Management. Front. Physiol., 13.","DOI":"10.3389\/fphys.2022.827678"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3361","DOI":"10.1210\/clinem\/dgaa513","article-title":"Anti-M\u00fcllerian Hormone and Ovarian Reserve: Update on Assessing Ovarian Function","volume":"105","author":"Moolhuijsen","year":"2020","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"76","DOI":"10.1186\/s13048-015-0204-9","article-title":"The Bologna criteria for poor ovarian response: A contemporary critical appraisal","volume":"8","author":"Younis","year":"2015","journal-title":"J. Ovarian Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"426","DOI":"10.1136\/oemed-2016-103953","article-title":"Occupational factors and markers of ovarian reserve and response among women at a fertility center","volume":"74","author":"Souter","year":"2017","journal-title":"Occup. Environ. Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1080\/19338244.2019.1577210","article-title":"Anti-M\u00fcllerian hormone levels in nurses working night shifts","volume":"75","author":"Johnson","year":"2020","journal-title":"Arch. Environ. Occup. Health"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"520","DOI":"10.1016\/j.fertnstert.2024.09.018","article-title":"Association between sleep quality and ovarian reserve in women of reproductive age: A cross-sectional study","volume":"123","author":"Lin","year":"2024","journal-title":"Fertil. Steril."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Kember, A.J., Elangainesan, P., Ferraro, Z.M., Jones, C., and Hobson, S.R. (2023). Common sleep disorders in pregnancy: A review. Front. Med., 10.","DOI":"10.3389\/fmed.2023.1235252"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"895","DOI":"10.1002\/ajim.23283","article-title":"Metabolic health measurements of shift workers in a national cross-sectional study: Results from the Canadian Health Measures Survey","volume":"64","author":"Harris","year":"2021","journal-title":"Am. J. Ind. Med."},{"key":"ref_18","unstructured":"Statistics Canada (2023, February 07). Usual Work Schedule at Current or Last Main Job and Scheduling Preferences, Persons Who Worked in 2018 or After, Canada (Provinces Only). Available online: https:\/\/www150.statcan.gc.ca\/n1\/daily-quotidien\/210322\/t005a-eng.htm."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"175","DOI":"10.2486\/indhealth.SW-3","article-title":"Working Time Society consensus statements: Psychosocial stressors relevant to the health and wellbeing of night and shift workers","volume":"57","author":"Fischer","year":"2019","journal-title":"Ind. Health"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1210\/er.2016-1083","article-title":"Circadian Rhythm and Sleep Disruption: Causes, Metabolic Consequences, and Countermeasures","volume":"37","author":"Potter","year":"2016","journal-title":"Endocr. Rev."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.jpsychores.2016.03.017","article-title":"Biological and psychological correlates of self-reported and objective sleep measures","volume":"84","author":"Jackowska","year":"2016","journal-title":"J. Psychosom. Res."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/12\/4769\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T05:23:14Z","timestamp":1782451394000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/12\/4769"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,19]]},"references-count":21,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["jcm15124769"],"URL":"https:\/\/doi.org\/10.3390\/jcm15124769","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,19]]}}}