Prostate and testicular growth analysis in human fetuses during the second gestational trimester

The second gestational trimester is a very important period for male genital development. We analyzed the testicular and prostatic volume growth and compared them to the biometric parameters in human fetuses.

We studied 64 testes and 32 prostates from 32 fetuses, aged 10-22 weeks postconception. Fetuses were evaluated regarding total length, crown-rump length, and bodyweight. The same observer performed all the measurements. After testicular and prostatic dissection, the prostate and testicular length, width and thickness were recorded with the aid of computer programs (Image Pro and ImageJ software, version 1.46r). Testicular volume (TV) and prostatic volume (PV) were calculated using the ellipsoid formula. Statistical analysis was performed with the GraphPad Prism program (version 6.01).

The fetuses presented PV between 6.1 and 297.18 mm²  (mean = 77.98 mm³ ). Linear regression analysis indicated that the PV in these fetuses increased significantly and positively with fetal age (r²  = .3120; p < .0001). We did not observe significant differences between the TV (right testis: 0.39-63.94 mm³ ; mean = 19.84 mm³ ; left testis: ​​​​​​0.52-55.37 mm³ , mean = 17.25 mm³ ). Linear regression analysis also indicated that the right and left TV (right: r²  = .6649; p < .0001 and left: r²  = .6792; p < .001) increased significantly and positively with fetal age.

The prostatic growth was slower during the second gestational trimester, with significant correlations with fetal biometric parameters. The testicular growth was moderate and showed a significant correlation with fetal parameters during the studied period in human fetuses.