{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T01:00:57Z","timestamp":1768352457137,"version":"3.49.0"},"reference-count":31,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T00:00:00Z","timestamp":1675814400000},"content-version":"vor","delay-in-days":38,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Reprod Medicine &amp; Biology"],"published-print":{"date-parts":[[2023,1]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Purpose<\/jats:title><jats:p>To investigate the relationship between the ratio of index to ring finger lengths (2D:4D ratio), reflecting androgen exposure in utero, and reproductive function among men.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Male patients (<jats:italic>N<\/jats:italic>\u00a0=\u00a0180) who consulted for fertility issues participated in the study. The palms of both hands were scanned, and the 2D:4D ratio was calculated. Data on semen volume, sperm concentration and total motility, total and motile sperm counts, and serum hormone concentrations were obtained. Spearman correlation coefficients between the 2D:4D ratio and hormone and semen quality parameters were calculated.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The total sperm count was significantly negatively correlated with the 2D:4D ratio of the left hand (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u22120.154, <jats:italic>p<\/jats:italic>\u2009\u00a0=\u00a00.039) but not with that of the right hand (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u22120.045, <jats:italic>p<\/jats:italic>\u2009\u00a0=\u00a00.548). Testosterone showed weak negative correlations with the 2D:4D ratio in the left (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u22120.142, <jats:italic>p<\/jats:italic>\u2009\u00a0=\u00a00.058) and right (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u2212 0.149, <jats:italic>p<\/jats:italic>\u2009\u00a0=\u00a00.046) hands. Follicle\u2010stimulating hormone levels were negatively correlated with the 2D:4D ratios of the left (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u22120.173, <jats:italic>p<\/jats:italic>\u2009\u00a0=\u00a00.020) and right (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u22120.164, <jats:italic>p<\/jats:italic>\u2009\u00a0=\u00a00.027) hands. Other semen quality parameters or luteinizing hormone levels showed no significant correlation with the 2D:4D ratios.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>No clear associations were observed between the 2D:4D ratios and reproductive function.<\/jats:p><\/jats:sec>","DOI":"10.1002\/rmb2.12500","type":"journal-article","created":{"date-parts":[[2023,2,9]],"date-time":"2023-02-09T06:51:57Z","timestamp":1675925517000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["The ratio of 2nd to 4th digit length and reproductive function of infertile male patients"],"prefix":"10.1002","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3174-4294","authenticated-orcid":false,"given":"Masahiro","family":"Uchida","sequence":"first","affiliation":[{"name":"Tsukuba Gakuen Hospital  Ibaraki Tsukuba Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teruaki","family":"Iwamoto","sequence":"additional","affiliation":[{"name":"International University of Health and Welfare  Otawara Tochigi Japan"},{"name":"Sanno Hospital  Minato Tokyo Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8414-2393","authenticated-orcid":false,"given":"Kazumitsu","family":"Yamasaki","sequence":"additional","affiliation":[{"name":"Tsukuba Gakuen Hospital  Ibaraki Tsukuba Japan"},{"name":"Sanno Hospital  Minato Tokyo Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fumiko","family":"Kariya","sequence":"additional","affiliation":[{"name":"Department of Human Ecology, School of International Health, Graduate School of Medicine The University of Tokyo  Bunkyo Tokyo Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7282-0863","authenticated-orcid":false,"given":"Shoko","family":"Konishi","sequence":"additional","affiliation":[{"name":"Department of Human Ecology, School of International Health, Graduate School of Medicine The University of Tokyo  Bunkyo Tokyo Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2023,2,8]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/16.5.972"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1210\/en.2009-0774"},{"key":"e_1_2_8_4_1","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/13.11.3000"},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.1186\/1477-7827-4-10"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.earlhumdev.2003.12.002"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1038\/36234"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.earlhumdev.2005.12.002"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/dei170"},{"key":"e_1_2_8_10_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2605.2010.01124.x"},{"key":"e_1_2_8_11_1","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/deg174"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.3109\/03014460.2014.902993"},{"key":"e_1_2_8_13_1","doi-asserted-by":"publisher","DOI":"10.1186\/1477-7827-9-57"},{"key":"e_1_2_8_14_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.psyneuen.2007.01.007"},{"key":"e_1_2_8_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.earlhumdev.2012.06.007"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/j.1939-4640.2003.tb03138.x"},{"issue":"3","key":"e_1_2_8_17_1","first-page":"211","article-title":"Second to fourth digit ratio (2D:4D) and testosterone in men","volume":"6","author":"Manning JT","year":"2004","journal-title":"Asian J Androl"},{"key":"e_1_2_8_18_1","doi-asserted-by":"publisher","DOI":"10.3390\/sexes3020020"},{"key":"e_1_2_8_19_1","volume-title":"The working Group for Creating Semen Analyses Standardization Guidelines","year":"2003"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1111\/andr.12983"},{"key":"e_1_2_8_21_1","volume-title":"World Health Organization, Department of Reproductive Health and Research","author":"WHO. World Health Organization","year":"2021"},{"key":"e_1_2_8_22_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajpa.10029"},{"key":"e_1_2_8_23_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10508-005-3121-y"},{"key":"e_1_2_8_24_1","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.20892"},{"key":"e_1_2_8_25_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0378-3782(02)00073-7"},{"key":"e_1_2_8_26_1","doi-asserted-by":"publisher","DOI":"10.3389\/fendo.2017.00041"},{"key":"e_1_2_8_27_1","doi-asserted-by":"publisher","DOI":"10.1006\/hbeh.2002.1830"},{"key":"e_1_2_8_28_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.2047-2927.2012.00013.x"},{"key":"e_1_2_8_29_1","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/deg198"},{"key":"e_1_2_8_30_1","doi-asserted-by":"publisher","DOI":"10.1017\/S2040174420001294"},{"key":"e_1_2_8_31_1","doi-asserted-by":"publisher","DOI":"10.1210\/jc.2008-1902"},{"key":"e_1_2_8_32_1","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.321.7264.789"}],"container-title":["Reproductive Medicine and Biology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/rmb2.12500","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/rmb2.12500","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/rmb2.12500","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,2,22]],"date-time":"2024-02-22T17:23:21Z","timestamp":1708622601000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/rmb2.12500"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,1]]},"references-count":31,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2023,1]]}},"alternative-id":["10.1002\/rmb2.12500"],"URL":"https:\/\/doi.org\/10.1002\/rmb2.12500","archive":["Portico"],"relation":{},"ISSN":["1445-5781","1447-0578"],"issn-type":[{"value":"1445-5781","type":"print"},{"value":"1447-0578","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,1]]},"assertion":[{"value":"2022-08-23","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-12-26","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2023-02-08","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e12500"}}