Urolithiasis is the main cause of obstruction in the lower urinary tract. Although it occurs in both males and females, urolithiasis is '''more common in mammalian males''' due to their long, narrow urethra. | Urolithiasis is the main cause of obstruction in the lower urinary tract. Although it occurs in both males and females, urolithiasis is '''more common in mammalian males''' due to their long, narrow urethra. |