Azoospermia

Azoospermia is a medical condition characterized by the absence of sperm in the ejaculate. It is diagnosed when semen analyses show no sperm after standard processing, typically on two separate occasions. Azoospermia accounts for an estimated 10–15% of male infertility cases and can have significant implications for fertility.

Azoospermia is commonly classified as obstructive azoospermia (OA) or nonobstructive azoospermia (NOA). OA results from a physical blockage in the reproductive tract that prevents sperm from reaching the ejaculate, while sperm production outside the blockage is usually normal. NOA reflects impaired sperm production within the testes, due to testicular failure, genetic disorders, hormonal problems, or prior chemotherapy or radiation.

Evaluation includes at least two semen analyses, a physical examination, and hormonal testing (follicle-stimulating hormone, luteinizing hormone, and testosterone). In OA, FSH is typically normal and testicular volume may be preserved; in NOA, FSH is often elevated and testicular size reduced. Imaging, such as scrotal ultrasound and transrectal ultrasound, helps identify obstruction, ejaculatory duct issues, or congenital absence of the vas deferens. Genetic testing (karyotype and Y-chromosome microdeletions) and CFTR gene testing may be indicated, especially in congenital absence or abnormalities of the vas deferens.

Management depends on the underlying cause. OA can sometimes be corrected surgically, and sperm retrieved from the epididymis or testes (PESA or TESA, often with microsurgical techniques) can be used with IVF–ICSI. NOA is managed with individualized approaches; sperm may be obtained with micro-TESE for use in IVF–ICSI in a subset of men. Hormonal therapy or varicocele repair may be considered in selected NOA cases. When fertility cannot be restored with the patient’s own sperm, options include donor sperm.

Prognosis varies by cause. OA generally has a higher likelihood of sperm retrieval and successful assisted reproduction than NOA. Ongoing monitoring for underlying conditions and genetic implications is recommended.