{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:21:22Z","timestamp":1760235682805,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,8]],"date-time":"2021-09-08T00:00:00Z","timestamp":1631059200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2020R1A2C4002477"],"award-info":[{"award-number":["NRF-2020R1A2C4002477"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Amniotic fluid is crucial for the well-being of the fetus. Recent studies suggest that dehydration in a pregnant woman leads to oligohydramnios. We assessed the variation in the amniotic fluid index (AFI) during the summer and non-summer seasons and evaluated neonatal outcomes. We retrospectively reviewed electrical medical records of pregnant women who visited the Konkuk University Medical Center for antenatal care, between July 2005 and July 2019. A total of 19,724 cases from 6438 singleton pregnant women were included after excluding unsuitable cases. All AFI values were classified as 2nd and 3rd trimester values. Additionally, borderline oligohydramnios (AFI, 5\u20138) and normal AFI (AFI, 8\u201324) were assessed according to the seasons. The average AFI between the summer and non-summer season was statistically different only in the 3rd trimester; but the results were not clinically significant. In the 3rd trimester, the summer season influenced the increased incidence of borderline oligohydramnios. The borderline oligohydramnios group showed an increased small-for-gestational-age (SGA) rate and NICU admission rate. In the summer season, the incidence of borderline oligohydramnios was seen to increase. This result would be significant for both physicians and pregnant women.<\/jats:p>","DOI":"10.3390\/ijerph18189483","type":"journal-article","created":{"date-parts":[[2021,9,8]],"date-time":"2021-09-08T10:12:03Z","timestamp":1631095923000},"page":"9483","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Does the Summer Season Affect the Amniotic Fluid Volume during Pregnancy?"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7539-2825","authenticated-orcid":false,"given":"Ah-Young","family":"Choi","sequence":"first","affiliation":[{"name":"Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul 05030, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun-Yi","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Korea University Guro Hospital, Korea University School of Medicine, Seoul 08308, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1835-0116","authenticated-orcid":false,"given":"In-Sook","family":"Sohn","sequence":"additional","affiliation":[{"name":"Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul 05030, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4449-0481","authenticated-orcid":false,"given":"Han-Sung","family":"Kwon","sequence":"additional","affiliation":[{"name":"Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul 05030, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong-Soo","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Sang-Gye Paik Hospital, Inje University School of Medicine, Seoul 01757, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Myoung-Hwan","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Sang-Gye Paik Hospital, Inje University School of Medicine, Seoul 01757, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seung-Woo","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Sang-Gye Paik Hospital, Inje University School of Medicine, Seoul 01757, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0622-0701","authenticated-orcid":false,"given":"Han-Sung","family":"Hwang","sequence":"additional","affiliation":[{"name":"Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul 05030, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1168","DOI":"10.1016\/0002-9378(90)90009-V","article-title":"The Amniotic Fluid Index in Normal Human Pregnancy","volume":"162","author":"Moore","year":"1990","journal-title":"Am. 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