The DOI matches its Crossref record; 2 of the 2 references it cites were found in a registry or an index.
The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen
Open accessAbstract
The differentiation of the urinogenital system and the appendicular skeleton in vertebrates is under the control of Hox genes. The common control of digit and gonad differentiation raises the possibility that patterns of digit formation may relate to spermatogenesis and hormonal concentrations. This work was concerned with the ratio between the length of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in right and left hands has a sexually dimorphic pattern; in males mean 2D:4D = 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal length. The dimorphism is present from at least age 2 years and 2D:4D is probably established in utero; (ii) high 2D:4D ratio in right hands was associated with germ cell failure in men (P = 0.04); (iii) sperm number was negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men testosterone concentrations were negatively related to right hand 2D:4D and in women and men LH (right hand), oestrogen (right and left hands) and prolactin (right hand) concentrations were positively correlated with 2D:4D ratio and (v) 2D:4D ratio in right hands remained positively related to luteinizing hormone and oestrogen after controlling for sex, age, height and weight.
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Citations
Cites
Sexual Differentiation of the Central Nervous System
MacLusky, N. J., & Naftolin, F. (1981) · Science · doi:10.1126/science.6163211 · Cited by 1,469
Neural Gonadal Steroid Actions
McEwen, B. S. (1981) · Science · doi:10.1126/science.6259728 · Cited by 438
Cited by
The Diagnosis of Polycystic Ovary Syndrome during Adolescence
Witchel, S. F., Oberfield, S., Rosenfield, R. L., Codner, E., Bonny, A., Ibáñez, L., Pena, A., Horikawa, R., Gomez-Lobo, V., Joel, D., et al. (2015) · Hormone Research in Paediatrics · doi:10.1159/000375530 · Cited by 3,113
Schmitt, D. P. (2005) · Behavioral and Brain Sciences · doi:10.1017/s0140525x05000051 · Cited by 974
Chamberlain (2005) · doi:10.1016/j.neubiorev.2004.11.004 · Cited by 529
Fetal testosterone and autistic traits
Auyeung, B., Baron‐Cohen, S., Ashwin, E., Knickmeyer, R., Taylor, K., & Hackett, G. (2009) · British Journal of Psychology · doi:10.1348/000712608x311731 · Cited by 462
Hönekopp, J., Bartholdt, L., Beier, L., & Liebert, A. (2007) · Psychoneuroendocrinology · doi:10.1016/j.psyneuen.2007.01.007 · Cited by 342
Metadata
- Authors
- Manning, J. T., Scutt, D., Wilson, J., & Lewis-Jones, D. I.
- Venue
- Human Reproduction
- Publisher
- Oxford University Press (OUP)
- Published
- 1998-11-01
- Volume
- 13
- Issue
- 11
- Pages
- 3000-3004
- ISSN
- 0268-1161 (ISSN-L)
- 1460-2350
- OpenAlex
- W2168152966
- Cited by
- 1,467
- References
- 2
- FWCI
- 1.80
- Type
- journal article
- Language
- en
- Open access
- bronze
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- CoChat. (2026). Citation check: The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen. https://app.cochat.ai/papers/10.1093/humrep/13.11.3000
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- Manning, J. T., Scutt, D., Wilson, J., & Lewis-Jones, D. I. (1998). The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen. Human Reproduction. https://doi.org/10.1093/humrep/13.11.3000
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
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