About Obstructive Azoospermia (OA)

Azoospermia refers to the complete absence of sperm in semen, accounting for 10% to 15% of male infertility cases. Its causes can be divided into two categories: obstructive azoospermia (OA) and non-obstructive azoospermia (NOA). The specific causes are as follows:
1. Obstructive azoospermia (OA)
(The testicles can produce sperm normally, but the sperm passage is blocked and cannot be discharged)
1. Congenital causes
• Congenital absence of the vas deferens (CBAVD): most commonly seen in patients with cystic fibrosis (CFTR gene mutation), bilateral vas deferens are not developed.
• Ejaculatory duct cyst or atresia: abnormal embryonic development leads to the inability to ejaculate semen.
2. Acquired causes
• Infection/inflammation: such as epididymitis, prostatitis, gonorrhea or tuberculosis leading to adhesion and blockage of the vas deferens.
• Iatrogenic injuries: complications of hernia surgery, prostate surgery, and vasectomy.
• Trauma: rupture of the vas deferens due to scrotal or pelvic trauma.