Does a Bilateral Polypropylene Mesh Alter the Duct Deferens Morphology, Testicular Size and Testosterone Levels? Experimental Study in Rats

Abstract Background The impact of hernia repair with a polypropylene (PP) mesh on testicular function and fertility remains uncertain, regardless of the technique used. This study evaluated the effect of a PP mesh on duct deferens morphology, testicular size and testosterone levels. Methods Forty adult male Wistar rats were distributed into groups according to the surgical procedure: 1) no surgery; 2) inguinotomy; 3) mesh placed on the duct deferens; and 4) mesh placed on the spermatic funiculus. After 90 postoperative days, the inguinal region was resected, and blood samples were collected for the measurement of serum testosterone (pg/dl). The testicle was measured with a pachymeter in the longitudinal and transverse directions to calculate its size (mm). The duct deferens were isolated and sectioned in three axial sections according to the relationship with the mesh — cranial, medial and caudal (1 cm above, at the segment where the mesh was placed, and 1 cm below, respectively). The wall thickness and duct deferens lumen area were measured. Results The morphology of the duct deferens was preserved in all groups. The mesh placement did not alter this morphology in any of the analyzed segments. In nonoperated animals, there was an anatomic reduction in the wall thickness of the duct deferens in the caudal segment (p<0.05 1/3 cranial and medial vs. caudal). Surgery, with or without mesh placement, did not alter the morphology, wall thickness or lumen area (p>0.05). In all operated groups, there was a decrease in testicle size (p<0.05); however, the serum testosterone levels were similar among the groups (p>0.05). Conclusion Surgery, with or without mesh placement, did not alter the morphology of the duct deferens and, although this treatment resulted in testicular size reduction, it did not affect serum testosterone levels. Future studies should deepen the analysis of the effect of the mesh on the functionality of these organs and the real impact on male fertility.