Appraisal of testicular volumes: volumes matching ultrasound values referenced to stages of genital development

Table 2 Findings for stages of genital development clinically testicular volumes by (W-ss)³ × 0.88*

Genital stage	Age range (years)	Testis width in scrotum (cm)	Testicular volume observed (ml)	Length of penis (cm) mean ± SD observed range	Hair stages
Genital stage	Age range (years)	Testis width in scrotum (cm)	Testicular volume observed (ml)	Length of penis (cm) mean ± SD observed range	Pubic hair	Other hair
1	Up to 13.25	<1.3	<1.27	Early childhood 4.8 ± 0.64 Observed 3.5 to 6.0	None
2	10 to 15	>1.5 to 2.1 ^#	>2.1 to 6.5 ^#	Early childhood 5.3 ± 0.75 Observed 4.0 to 6.5	None or sparse growth of downy or curled at the base of penis	Early pubic hair is usually from adrenarche
3	11.4 to 15	>2.0 to 2.2^#	4.6 to 7.4^#	Growth of penis 7.4 ± 0.49 Observed 7.0 to 8.0	No hair to sparse growth of darker and curlier	Pubic & axillary hair from adrenarche & gonadarche
4	11.6 to 17	>2.1 to 2.6^#	6 to 12.3^#	Development of glans 8.6 ± 1.29 Observed 6.5 to 12.0 cm	Abundant but not filling whole pubic area	As above, Not in inner thigh
5	13 to 17.5	>2.5 to 3.1 ^#	10.7 to 21.4^#	9.5 ± 0.99 Observed 7.5 to 11.0	Adult, abundant, inverse triangle	Inner thigh No in lineal alba
Adult	> 16	>2.5 to 3.1	10.6 to 21.2	9.7 ± 1.01 Observed 8.0 to 11.0	Abundant	Linea alba abdomen or chest or beard from gonadarche

For testicular volumes calculated by W x H x L × 0.52, divide Values reported by 1.365 (0.71/0.52 = 1.365). The findings were obtained as indicated in the methods. The width of the testis was measured. The stage of genital development (testes, scrotum and penis only) as defined by Tanner, and range of years were identified. Testicular volumes were calculated. Penile length was measured. Pubic and other hair observed was recorded, but not included in determining stages 1 to 5 of genital development
# = p < 0.0001
* Testicular volumes obtained by (W-ss)³ × 0.88, equivalent to ultrasound volumes calculated by W x H x L × 0.71
Most helpful findings are bolded

ISSN: 1687-9856