Which condition can lead to obstruction in male fertility?

• A. Mumps orchitis.
• B. Seasonal allergies.
• C. Vitamin C deficiency.
• D. Hyperthyroidism.

Answer: (A)

Obstruction of sperm flow in men most often arises from scarring after inflammation of the reproductive ducts. When mumps involves the testes (orchitis), the inflammatory process can damage the seminiferous tubules and surrounding ducts, leading to scar tissue that blocks the passage of sperm. This can cause obstructive infertility because sperm can't travel normally to the ejaculate, even if sperm production elsewhere is unaffected. The other options don’t produce a blockage in the ductal system: seasonal allergies affect the respiratory tract, vitamin C deficiency produces systemic symptoms without causing ductal obstruction, and hyperthyroidism affects hormonal balance rather than causing a physical obstruction in the reproductive tract.