Male infants with hypospadias and/or cryptorchidism show a lower 2D/4D digit ratio than normal boys

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O Abbo1, C Ferdynus2, N Kalfa3

  • 1Department of Pediatric Surgery, CHU F Guyon, Bellepierre, Saint-Denis de La Réunion, Reunion Island, France.

Archives of Disease in Childhood
|February 18, 2015
PubMed

Insights

Boys with genital abnormalities like cryptorchidism and hypospadias show a lower 2D:4D digit ratio. This ratio, the index finger to ring finger length, may indicate altered prenatal androgen exposure in these conditions.

Area of Science:

  • Endocrinology
  • Human Biology
  • Developmental Biology

Background:

  • The 2D:4D digit ratio (index finger to ring finger) is sexually dimorphic in humans, with higher ratios in females, potentially linked to prenatal androgen exposure.
  • Congenital adrenal hyperplasia in children supports the link between prenatal androgens and the 2D:4D ratio.
  • Normal male genital development is influenced by in-utero androgen activity.

Purpose of the Study:

  • To investigate whether the 2D:4D digit ratio is altered in boys diagnosed with cryptorchidism or hypospadias.
  • To compare the 2D:4D digit ratio in boys with genital anomalies to that of normal boys and girls.

Main Methods:

  • A prospective study enrolled prepubertal boys with cryptorchidism or hypospadias.
  • The 2D:4D digit ratio was measured and compared between patient groups and two control cohorts (normal boys and normal girls).
  • Interobserver and intraobserver variability for 2D:4D ratio measurements were assessed.

Main Results:

  • The study included 57 boys with hypospadias/cryptorchidism, 79 normal boys, and 25 normal girls.
  • A statistically significant difference in the mean 2D:4D digit ratio was observed across the three groups (p<0.0001).
  • Boys with genital anomalies exhibited a lower 2D:4D digit ratio compared to both normal boys and normal girls.

Conclusions:

  • Boys presenting with genital abnormalities, specifically cryptorchidism and/or hypospadias, demonstrate a lower 2D:4D digit ratio.
  • This finding suggests a potential association between a lower 2D:4D ratio and the presence of these specific genital anomalies in males.
Abstract

Keywords:
EndocrinologyGeneral PaediatricsNeonatologyPaediatric Surgery

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