{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T11:32:45Z","timestamp":1788867165586,"version":"build-2803163510"},"reference-count":29,"publisher":"Wiley","issue":"7","license":[{"start":{"date-parts":[[2025,5,15]],"date-time":"2025-05-15T00:00:00Z","timestamp":1747267200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Acta Obstet Gynecol Scand"],"published-print":{"date-parts":[[2025,7]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Introduction<\/jats:title><jats:p>Preterm birth is subject to seasonal periodicity, dependent on geographical, meteorological, and environmental factors. This study aims to assess whether preterm birth in the Netherlands is subject to seasonal periodicity.<\/jats:p><\/jats:sec><jats:sec><jats:title>Material and Methods<\/jats:title><jats:p>We performed a population\u2010based cohort including singleton births between January 1, 2010 and December 31, 2019 between 24\u2009+\u20090 and 42\u2009+\u20096\u2009weeks of gestation in the Netherlands. The primary outcome was the incidence of preterm birth &lt;37\u2009weeks. Secondary outcomes were total, spontaneous, and iatrogenic preterm birth &lt;28, &lt;32, and &lt;37\u2009weeks of gestation. Preterm birth incidence was calculated per conception month and as a proportion of fetuses\u2010at\u2010risk, taking into account the number of ongoing pregnancies at risk for preterm birth. The incidence of preterm birth &lt;37\u2009weeks per conception month and out of fetuses\u2010at\u2010risk was plotted for the 10\u2010year study period. Incidences were reported as rates, and seasonality was tested with logistic regression and autocorrelation function with a 12\u2010month lag.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>In total, 1\u2009598\u2009554 births were included in the 10\u2010year study period. The average monthly birth count varied from 12\u2009006 (February) to 14\u2009293 (September). The average monthly preterm birth count varied from 610 (February) to 728 (July). Over the total study period, the incidence of preterm birth &lt;37\u2009weeks was 5.16%. Pregnancies conceived in April and May had the highest incidences of preterm birth &lt;37\u2009weeks (5.58% and 5.38%, respectively). Out of fetuses\u2010at\u2010risk, preterm birth incidences were highest in October, December, and January (between 1.38% and 1.42%) and lowest in February (1.22%) and April (1.22%). The ten\u2010year incidence of preterm birth &lt;37\u2009weeks revealed a consistent seasonal pattern, with annually recurrent peaks in preterm birth incidence each year (<jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>In the Netherlands, the incidence of preterm birth in singletons is subject to seasonal periodicity. Conception in April and May is associated with the highest risk of preterm birth. Fetuses are at the highest risk for preterm birth from October to January and at the lowest risk in February and April.<\/jats:p><\/jats:sec>","DOI":"10.1111\/aogs.15134","type":"journal-article","created":{"date-parts":[[2025,5,15]],"date-time":"2025-05-15T10:40:45Z","timestamp":1747305645000},"page":"1286-1294","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Seasonal patterns of preterm birth in the Netherlands: A population\u2010based cohort study"],"prefix":"10.1111","volume":"104","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2083-0285","authenticated-orcid":false,"given":"Annabelle L.","family":"van Gils","sequence":"first","affiliation":[{"name":"Amsterdam UMC, Department of Obstetrics and Gynecology University of Amsterdam  Amsterdam The Netherlands"},{"name":"Amsterdam Reproduction and Development Research Institute  Amsterdam The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita C.","family":"Ravelli","sequence":"additional","affiliation":[{"name":"Amsterdam UMC, Department of Obstetrics and Gynecology University of Amsterdam  Amsterdam The Netherlands"},{"name":"Amsterdam Reproduction and Development Research Institute  Amsterdam The Netherlands"},{"name":"Amsterdam UMC, Department of Medical Informatics University of Amsterdam  Amsterdam The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brenda M.","family":"Kazemier","sequence":"additional","affiliation":[{"name":"Amsterdam UMC, Department of Obstetrics and Gynecology University of Amsterdam  Amsterdam The Netherlands"},{"name":"Amsterdam Reproduction and Development Research Institute  Amsterdam The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eva","family":"Pajkrt","sequence":"additional","affiliation":[{"name":"Amsterdam UMC, Department of Obstetrics and Gynecology University of Amsterdam  Amsterdam The Netherlands"},{"name":"Amsterdam Reproduction and Development Research Institute  Amsterdam The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martijn A.","family":"Oudijk","sequence":"additional","affiliation":[{"name":"Amsterdam Reproduction and Development Research Institute  Amsterdam The Netherlands"},{"name":"Amsterdam UMC, Department of Obstetrics and Gynecology Vrije Universiteit Amsterdam  Amsterdam The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2025,5,15]]},"reference":[{"key":"e_1_2_13_2_1","doi-asserted-by":"publisher","DOI":"10.1055\/s-0035-1571202"},{"key":"e_1_2_13_3_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12916-023-03171-4"},{"key":"e_1_2_13_4_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0040228"},{"key":"e_1_2_13_5_1","doi-asserted-by":"publisher","DOI":"10.3390\/ijerph110100091"},{"key":"e_1_2_13_6_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-3016.2008.00971.x"},{"key":"e_1_2_13_7_1","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2393-14-310"},{"key":"e_1_2_13_8_1","doi-asserted-by":"publisher","DOI":"10.1093\/oxfordjournals.aje.a113679"},{"key":"e_1_2_13_9_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1471-0528.2006.01055.x"},{"key":"e_1_2_13_10_1","doi-asserted-by":"publisher","DOI":"10.1093\/ije\/dyv100"},{"key":"e_1_2_13_11_1","doi-asserted-by":"publisher","DOI":"10.3346\/jkms.2016.31.11.1797"},{"key":"e_1_2_13_12_1","first-page":"919","article-title":"Geographic differences in seasonality of preterm births in Japan","volume":"70","author":"Matsuda S","year":"1998","journal-title":"Hum Biol"},{"key":"e_1_2_13_13_1","doi-asserted-by":"publisher","DOI":"10.1093\/ajcn\/81.1.134"},{"key":"e_1_2_13_14_1","doi-asserted-by":"publisher","DOI":"10.1111\/aogs.14684"},{"key":"e_1_2_13_15_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1471-0528.2011.03010.x"},{"key":"e_1_2_13_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ejogrb.2020.02.021"},{"key":"e_1_2_13_17_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2021.45800"},{"key":"e_1_2_13_18_1","unstructured":"European Centre for Disease Prevention and Control.Seasonal influenza 2018\u20132019 Annual Epidemiological Report Key facts(2)\u2010annotated.pdf.2020https:\/\/www.ecdc.europa.eu\/en\/publications\u2010data\/"},{"key":"e_1_2_13_19_1","unstructured":"European Centre for Disease Prevention and Control.Seasonal influenza 2017\u20132018. 2018 annotated.pdf.https:\/\/www.ecdc.europa.eu\/en\/publications\u2010data\/"},{"key":"e_1_2_13_20_1","volume-title":"Perinatale Zorg in Nederland anno 2020: duiding door landelijke perinatale audit en registratie [Perinatal Care in the Netherlands in 2020: interpretation by national perinatal audit and registration]","author":"PERINED","year":"2020"},{"key":"e_1_2_13_21_1","article-title":"Perinataal beleid bij extreme vroeggeboorte [Perinatal policy for extreme prematurity]","volume":"157","author":"Kluiver EOM","year":"2013","journal-title":"Ned Tijdschr Geneeskd"},{"key":"e_1_2_13_22_1","doi-asserted-by":"publisher","DOI":"10.1097\/EDE.0b013e3181a66e96"},{"key":"e_1_2_13_23_1","doi-asserted-by":"publisher","DOI":"10.21037\/tp-23-134"},{"key":"e_1_2_13_24_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12884-023-05636-z"},{"key":"e_1_2_13_25_1","doi-asserted-by":"publisher","DOI":"10.1289\/ehp.1510810"},{"key":"e_1_2_13_26_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12884-025-07210-1"},{"key":"e_1_2_13_27_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ajog.2004.06.092"},{"key":"e_1_2_13_28_1","doi-asserted-by":"publisher","DOI":"10.1111\/aogs.13786"},{"key":"e_1_2_13_29_1","volume-title":"Griepvaccinatie: herziening van de indicatiestelling. Den Haag: Gezondheidsraad [Flu vaccination: revision of the indication]","author":"Gezondheidsraad","year":"2021"},{"key":"e_1_2_13_30_1","doi-asserted-by":"publisher","DOI":"10.1002\/jmv.22181"}],"container-title":["Acta Obstetricia et Gynecologica Scandinavica"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/aogs.15134","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,7]],"date-time":"2025-06-07T10:37:14Z","timestamp":1749292634000},"score":1,"resource":{"primary":{"URL":"https:\/\/obgyn.onlinelibrary.wiley.com\/doi\/10.1111\/aogs.15134"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,15]]},"references-count":29,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2025,7]]}},"alternative-id":["10.1111\/aogs.15134"],"URL":"https:\/\/doi.org\/10.1111\/aogs.15134","archive":["Portico"],"relation":{},"ISSN":["0001-6349","1600-0412"],"issn-type":[{"value":"0001-6349","type":"print"},{"value":"1600-0412","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,15]]},"assertion":[{"value":"2024-09-24","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-04-07","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-05-15","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}