{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:24:06Z","timestamp":1772252646906,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T00:00:00Z","timestamp":1615248000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>To establish whether serum bilirubin levels vary in healthy term neonates according to seasonal variations and meteorological factors, we retrospectively studied 3344 healthy term neonates born between 2013 and 2018. Total serum bilirubin (TSB) levels were measured on the fourth day after birth. The monthly and seasonal variations in TSB levels and clinical and meteorological effects on TSB levels were assessed. In the enrolled neonates, the median TSB level was 195 \u00b5mol\/L. The TSB level peaked in December and was the lowest in July, but the variation was not statistically significant. The TSB level was significantly higher in the cold (October to March) than in the warm season (April to September; p = 0.01). The comparison between seasonal differences according to sex showed TSB levels were significantly higher in the cold than in the warm season in male infants (p = 0.001), whereas no significant difference was observed in female infants. A weakly negative but significant association existed between TSB levels and the mean daily air temperature (r = \u22120.07, p = 0.007) in only the male population; the female population showed no significant correlation between TSB levels and meteorological parameters. The season of birth is an etiological factor in neonatal jaundice, with an additional influence from sex.<\/jats:p>","DOI":"10.3390\/ijerph18052763","type":"journal-article","created":{"date-parts":[[2021,3,9]],"date-time":"2021-03-09T06:22:32Z","timestamp":1615270952000},"page":"2763","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Effects of Season of Birth and Meteorological Parameters on Serum Bilirubin Levels during the Early Neonatal Period: A Retrospective Chart Review"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3391-3757","authenticated-orcid":false,"given":"Shigeo","family":"Iijima","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu 4313192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Toru","family":"Baba","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu 4313192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miyuki","family":"Kondo","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu 4313192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomoka","family":"Fujita","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu 4313192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akira","family":"Ohishi","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu 4313192, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,9]]},"reference":[{"key":"ref_1","unstructured":"Kliegman, R.M., and St. Geme, J.W. (2019). Jaundice and Hyperbilirubinemia in The Newborn. Nelson Textbook of Pediatrics, Elsevier. [21st ed.]."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1159\/000244422","article-title":"Influence of bilirubin on the antioxidant capacity of plasma in newborn infants","volume":"71","author":"Lavoie","year":"1997","journal-title":"Biol. Neonate"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1097\/01.PCC.0000154961.37833.79","article-title":"Does gender affect neonatal hyperbilirubinemia in low-birth-weight infants?","volume":"6","author":"Tioseco","year":"2005","journal-title":"Pediatr. Crit. Care Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1016\/j.jpeds.2014.01.060","article-title":"Bilirubin uridine diphosphate-glucuronosyltransferase variation is a genetic basis of breast milk jaundice","volume":"165","author":"Maruo","year":"2014","journal-title":"J. Pediatr."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1097\/JOM.0b013e318193e12e","article-title":"Identifying vulnerable subpopulation for climate change health effects in the United States","volume":"51","author":"Balbus","year":"2009","journal-title":"J. Occup. Environ. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1006\/abbi.1998.0584","article-title":"Bilirubin is an effective antioxidant of peroxynitre-mediated protein oxidation in human blood plasma","volume":"352","author":"Minetti","year":"1998","journal-title":"Arch. Biochem. Biophys."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"601","DOI":"10.1542\/peds.43.4.601","article-title":"Seasonal neonatal hyperbilirubinemia","volume":"43","author":"Milby","year":"1969","journal-title":"Pediatrics"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1111\/j.1471-0528.1970.tb03568.x","article-title":"Neonatal jaundice in Chinese newborns","volume":"77","author":"Lee","year":"1970","journal-title":"J. Obstet. Gynaecol. Br. Commnw."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1136\/adc.50.2.156","article-title":"Effect of seasonal variation in daylight on bilirubin level in premature infants","volume":"50","author":"Anttolainen","year":"1975","journal-title":"Arch. Dis. Child."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1235","DOI":"10.1136\/bmj.1.6122.1235","article-title":"Factors influencing the incidence of neonatal jaundice","volume":"1","author":"Friedman","year":"1978","journal-title":"Br. Med. J."},{"key":"ref_11","first-page":"403","article-title":"Diferencias estacionales en la ictericia neonatal [Seasonal differences in neonatal jaundice]","volume":"45","year":"1996","journal-title":"An. Esp. Pediatr."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1076\/0929-1016(200002)31:1;1-0;FT050","article-title":"Season of birth and early neonatal events. The rise of serum bilirubin","volume":"31","author":"Bottini","year":"2000","journal-title":"Biol. Rhythm. Res."},{"key":"ref_13","first-page":"344","article-title":"An epidemiological survey on neonatal jaundice in China","volume":"114","author":"Ding","year":"2001","journal-title":"Chin. Med. J."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1076\/brhm.34.1.13.14077","article-title":"Seasonal pattern of phototherapy: A study in the Sardinian population","volume":"34","author":"Bottini","year":"2003","journal-title":"Biol. Rhythm. Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1203\/00006450-201011001-01185","article-title":"Seasonal nature of neonatal jaundice","volume":"68","author":"Cerna","year":"2010","journal-title":"Pediatr. Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1317","DOI":"10.1111\/tmi.12189","article-title":"Incidence of and risk factors for neonatal jaundice among newborns in south Nepal","volume":"18","author":"Scrafford","year":"2013","journal-title":"Trop. Med. Int. Health"},{"key":"ref_17","first-page":"708","article-title":"Effect of fetal sex and seasonal variation on the level of neonatal hyperbilirubinemia","volume":"4","author":"Armady","year":"2015","journal-title":"Curr. Sci. Int."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"50","DOI":"10.4103\/2321-4848.154945","article-title":"Variation in the serum bilirubin levels in newborns according to gender and seasonal changes","volume":"3","author":"Bala","year":"2015","journal-title":"Arch. Med. Health Sci."},{"key":"ref_19","first-page":"424","article-title":"Risk factors for neonatal hyperbilirubinemia","volume":"76","author":"Phuapradit","year":"1993","journal-title":"J. Med. Assoc. Thail."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1177\/000456329102800202","article-title":"The analysis of bilirubin in serum","volume":"28","author":"Westwood","year":"1991","journal-title":"Ann. Clin. Biochem."},{"key":"ref_21","unstructured":"Japan Meteorological Agency (2020, May 07). Weather, Climate & Earthquake Information, Available online: http:\/\/www.jma.go.jp\/jma\/indexe.html."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"30","DOI":"10.5742\/MEWFM.2018.93301","article-title":"Investigating the relationship between serum bilirubin levels in the first week of life with season of birth","volume":"16","author":"Hojat","year":"2018","journal-title":"World Fam. Med."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1094","DOI":"10.1016\/S0140-6736(58)91849-X","article-title":"Influence of light on the hyperbilirubinaemia of infants","volume":"1","author":"Cremer","year":"1958","journal-title":"Lancet"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Iijima, S., Sekii, K., Baba, T., Ueno, D., and Ohishi, A. (2016). Seasonal variation in the international normalized ratio of neonates and its relationship with ambient temperature. BMC Pediatr., 16.","DOI":"10.1186\/s12887-016-0639-1"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"847","DOI":"10.1038\/nn1276","article-title":"Epigenetic programming by maternal behavior","volume":"7","author":"Weaver","year":"2004","journal-title":"Nat. Neurosci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"834","DOI":"10.1124\/dmd.108.024224","article-title":"Mechanism of gender-divergent UDP-glucuronosyltransferase mRNA expression in mouse liver and kidney","volume":"37","author":"Buckley","year":"2009","journal-title":"Drug Metab. Dispos."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1016\/0016-5085(84)90705-4","article-title":"Influence of sex and sex steroids on bilirubin uridine diphosphate-glucuronosyltransferase activity of rat liver","volume":"87","author":"Muraca","year":"1984","journal-title":"Gastroenterology"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1016\/j.arcmed.2018.05.001","article-title":"Seasonal variations in cerebral palsy births","volume":"49","author":"Sienkiewicz","year":"2018","journal-title":"Arch. Med. Res."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Li, S., Wang, J., Xu, Z., Wang, X., Xu, G., Zhang, J., Shen, X., and Tong, S. (2018). Exploring associations of maternal exposure to ambient temperature with duration of gestation and birth weight: A prospective study. BMC Pregnancy Childbirth, 18.","DOI":"10.1186\/s12884-018-2100-y"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1137","DOI":"10.1007\/s00360-017-1088-3","article-title":"Effects of heat stress on the renal and branchial carbohydrate metabolism and antioxidant systemof Antarctic fish","volume":"187","author":"Forgati","year":"2017","journal-title":"J. Comp. Physiol. B"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1016\/j.earlhumdev.2005.03.013","article-title":"Seasonal fluctuations in birth weight and neonatal limb length; does prenatal vitamin D influence neonatal size and shape?","volume":"81","author":"McGrath","year":"2005","journal-title":"Early Hum. Dev."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"383","DOI":"10.3945\/ajcn.112.055426","article-title":"Maternal serum 25-hydroxyvitamin D and placental vascular pathology in a multicenter US cohort","volume":"98","author":"Gernand","year":"2013","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_33","first-page":"82","article-title":"Epidemiology of neonatal jaundice in the Jerusalem population","volume":"10","author":"Gale","year":"1990","journal-title":"J. Pediatr. Gastroenterol. Nutr."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"824","DOI":"10.1111\/j.1651-2227.1989.tb11157.x","article-title":"Difference in TcB readings between full term newborn infants born vaginally and by cesarean section","volume":"78","author":"Yamauchi","year":"1989","journal-title":"Acta. Paediatr. Scand."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"993","DOI":"10.1111\/j.1651-2227.2010.01761.x","article-title":"Effect of anaesthetic agents administered to the mothers on transcutaneous bilirubin levels in the neonates","volume":"99","author":"Alkan","year":"2010","journal-title":"Acta. Paediatr."},{"key":"ref_36","first-page":"187","article-title":"A case report of Gilbert syndrome","volume":"1","author":"Manandhar","year":"2003","journal-title":"Kathmandu Univ. Med. J."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"656","DOI":"10.1016\/S0022-3476(98)70356-7","article-title":"Gilbert syndrome accelerates development of neonatal jaundice","volume":"132","author":"Bancroft","year":"1998","journal-title":"J. Pediatr."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"578","DOI":"10.1016\/S0140-6736(96)91273-8","article-title":"Genetic variation in bilirubin UPD-glucuronosyltransferase gene promoter and Gilbert\u2019s syndrome","volume":"347","author":"Monaghan","year":"1996","journal-title":"Lancet"},{"key":"ref_39","first-page":"73","article-title":"Gly71Arg mutation of the bilirubin UDP-glucuronosyltransferase 1A1 gene is associated with neonatal hyperbilirubinemia in the Japanese population","volume":"48","author":"Yamamoto","year":"2002","journal-title":"Kobe J. Med. Sci."}],"container-title":["International Journal of Environmental Research and Public Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/5\/2763\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:35:25Z","timestamp":1760160925000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-4601\/18\/5\/2763"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,3,9]]},"references-count":39,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["ijerph18052763"],"URL":"https:\/\/doi.org\/10.3390\/ijerph18052763","relation":{"has-preprint":[{"id-type":"doi","id":"10.21203\/rs.3.rs-88016\/v1","asserted-by":"object"}]},"ISSN":["1660-4601"],"issn-type":[{"value":"1660-4601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,3,9]]}}}