Introduction. Recently, decrease in male reproductive function has become particularly relevant. Nowadays, 8 to 29% of married couples are infertile throughout the world.
The purpose of our study was the ascertainment of the peculiarities of development of seminal vesicles, seminal and ejaculatory ducts.
Material and methods. The study was carried out on 16 series of histological sections of pre-fetuses of 10-12 weeks and 4-month fetuses. Nine waxed reconstructions of pelvic organs of pre-fetuses of 65.0 mm parietococcygeal length (PCL) and fetuses of 82.0, 85.0, 95.0 and 130.0 mm PCL were made and studied.
Results. In pre-fetuses of 46.0-52.0 mm PCL, the mesonephric duct (wolffian duct) is reduced in the cranial and middle sections. The diameter of the unreduced portion of the wolffian duct at the gonad level varies from 58 to 68 μm. At the beginning of the fetal period of ontogenesis, the length of the right seminal vesicle is 1.56 ± 0.12 mm, its width is 0.54 ± 0.05 mm, its thickness is 0.46 ± 0.06 mm. The dimensions of the left seminal vesicle are accordingly: 1.39 ± 0.11, 0.61 ± 0.05 and 0.57 ± 0.06 mm. In fetus of 130.0 mm PCL, the seminal vesicles are represented by the main tubule and its branches. The length of the right seminal vesicle is 2.3 mm, and the left is 2.2 mm. The length of the cavity of the main duct of the right seminal vesicle is 4.6 mm, and 6.4 mm including the branches. The length of the cavity of the main duct of the left seminal vesicle is 4.8 mm, and 5.6 mm including the branches.
Conclusions. At the end of the 10th – the beginning of the 11th week of prenatal development, intensive upgrowth of the caudal parts of the mesonephric ducts was noted, resulting in the seminal ducts, seminal vesicles and prostate excretory ducts appearance. In the fetuses of 95.0 120.0 mm of PCL, formation of an ampulla of the seminal duct was observed. At the end of the 4th month of prenatal development, the external and internal structure of the seminal vesicles and ampullae of the seminal duct becomes more complicated.
Key words: seminal vesicle, seminal duct, ejaculatory duct, morphogenesis.