Korean J Urol.  2010 Mar;51(3):208-211.

Is the Index Finger and Ring Finger Ratio (2D:4D) Reliable Predictor of Semen Quality?

• Seo H
• Kim KY
• Rho J

Abstract

PURPOSE
The purpose of this paper is to test the validity of hypothesis that the index finger and ring finger ratio (2D:4D) is related with men's semen quality. MATERIALS AND METHODS: We set two groups of healthy young male student (mean age 23.9) who have different 2D:4D ratio from different departments of Chosun University. One group consists of 26 men whose 2D:4D ratio is higher than 1 (mean 1.06), and the other group consists of 33 men whose 2D:4D ratio is lower than 1 (mean 0.94). Their semen was collected by masturbation and examined. RESULTS: A comparative analysis revealed that there is no relation between semen quality and the 2D:4D ratio. The group of 2D:4D> or =1 showed a semen volume of 3.66+/-1.64 ml, on the other hand, the group of 2D:4D<1 showed a semen volume of 3.73+/-1.40 ml. No statistical correlation was found (p=0.82). The view of sperm count and motile sperm in single ejaculated semen also showed no statistically significance with 2D:4D ratio (p=0.84, p=0.43, respectively). CONCLUSIONS: The 2D:4D ratio has no statistically significant correlation with the semen quality of health young male. Thus, measurements of finger length cannot be a reliable indicator of semen quality and testicular function.

Keyword

Fingers; Semen analysis

MeSH Terms

Fingers
Hand
Humans
Male
Masturbation
Semen
Semen Analysis
Sperm Count
Spermatozoa

Figure

• 

  FIG. 1 The scatter plot shows that there was no correlation between finger ratio and the semen quality-semen volume, sperm count and motile sperm. If the dots in scatter plot are gathered to the median transverse curved line, the data has statistically significant more.

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