The growth of the testes during the fetal period.

Abstract

To determine the size and position of the fetal testes during gestation. The study comprised 48 testes obtained from 24 human fetuses with no congenital abnormalities, aged 14-40 weeks. The development of the fetuses was evaluated by measuring the crown-rump length. Testicular size was assessed as the height, width, thickness and weight, and the position of testes determined during fetal development. The testes in 11 fetuses (22 testes) aged 14-37 weeks were in the abdominal cavity; no testis had descended to the scrotum in any fetus until 27 weeks of gestation. Both testes had descended to the scrotum only in fetuses aged 33-40 weeks. There was no significant difference between right and left testicular size in 13 fetuses (26 testes) aged 27-40 weeks, but size correlated with gestational age (P<0.001). All testes had descended to the scrotum by 33 weeks of gestation, but there was considerable variation in position from 27 weeks.