Second to fourth digit ratio (2D:4D) in men attending Infertility Clinics in Akure Metropolis Nigeria: a predictive index?

ABSTRACT

The ratio of index finger length to ring finger length is called the “2D4D digit ratio,” or more simply, the “digit ratio”. This study was to investigate if there are ignificant differences in the digit ratio (2D4D) of infertile men attending an infertility clinic and men drawn from the general population in Akure Nigeria; to generate data locally to serve as a source for future referencing in anthropometry as it relates to male fertility assessment. A total of 84 participants were involved in this study. They include men attending an infertility clinic (n=42), and those drawn randomly from the general population (n=42) with regards to their fertility. Information on 2D4D and the seminal fluid data from two samples were obtained. Direct digit estimates was done using digital calipers and indirectly by taking measurements from a digital image of the hand. The digit ratios were obtained by dividing the lengths, of the index finger by the ring finger. Semen was collected from each participant by masturbation and examined for count and motility to ascertain their fertility status. There was a statistically significant (p < 0.05) increase in the length of the fourth digit compared to the second digit in fertile men. The 2D4D ratio in fertile men was significantly lower (p < 0.05) compared to infertile men. This study demonstrates an association between 2D4D ratio and the fertility status in adult men in Akure metropolis Nigeria.