Last reviewed: 28 Dec 2021
Last updated: 14 May 2020



History and exam

Key diagnostic factors

  • inability of a couple to conceive
  • vasectomy
  • palpable and dilated testicular veins
  • erectile dysfunction and decreased libido
  • testis atrophy (testis smaller than 20 cm^3)
  • body habitus, abnormal hair distribution, and gynecomastia
  • absent vasa or epididymis

Other diagnostic factors

  • headaches, galactorrhea, and visual disturbance
  • anosmia
  • frequent respiratory infections
  • pain, blood, or pus with ejaculation

Risk factors

  • varicocele
  • cryptorchidism
  • prior chemotherapy or radiation therapy
  • current medications
  • cystic fibrosis and congenital bilateral absence of vas deferens (CBAVD)
  • Y chromosome abnormalities
  • Klinefelter syndrome (47,XXY)
  • endocrinopathy
  • genital tract infection
  • erectile dysfunction
  • previous infertility
  • retrograde ejaculation
  • obesity
  • testicular torsion or trauma
  • lifestyle including smoking and alcohol consumption
  • exposure to androgen
  • age >55 years
  • environmental toxin exposure
  • hx of CAD or diabetes
  • hx of STD
  • hot tub use

Diagnostic investigations

1st investigations to order

  • sperm concentration
  • sperm motility
  • sperm morphology
  • seminal fluid parameters

Investigations to consider

  • sperm viability
  • sperm membrane function
  • hormonal assays
  • MRI of the pituitary and hypothalamus
  • color flow Doppler imaging
  • urine testing for retrograde ejaculation
  • genetic analysis
  • sperm DNA assays
  • antisperm antibody serology
  • acrosome reaction test
  • sperm penetration assay (hamster egg penetration test)
  • sperm longevity test
  • electron microscopy
  • testicular biopsy

Treatment algorithm



Ali A. Dabaja, MD

Director of Male Reproductive Medicine and Sexual Medicine

Henry Ford Health System

K9 Urology Clinic




AAD declares that he has no competing interests.

Ahmad O. Hammoud, MD, MPH

Medical Director

IVF Michigan Fertility Center

Bloomfield Hills



AOH declares that he has no competing interests.


Dr Ali A. Dabaja and Dr Ahmad O. Hammoud would like to gratefully acknowledge Dr Benjamin Emery, the previous contributor to this monograph. BE declares that he has no competing interests.

Peer reviewers

Peter N. Kolettis, MD

Associate Professor

Division of Urology

University of Alabama at Birmingham




PNK declares that he has no competing interests.

Use of this content is subject to our disclaimer