Male factor infertility

Last reviewed: 25 Aug 2023
Last updated: 03 Mar 2022



History and exam

Key diagnostic factors

  • inability of an opposite-sex couple to conceive
  • vasectomy
  • palpable and dilated testicular veins
  • erectile dysfunction and decreased libido
  • testis atrophy (testis smaller than 20 cm³)
  • body habitus, abnormal hair distribution, and gynecomastia
  • absent vasa or epididymis
More key diagnostic factors

Other diagnostic factors

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

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
  • previous infertility
  • genital tract infection
  • erectile dysfunction
  • retrograde ejaculation
  • obesity
  • testicular torsion or trauma
  • lifestyle factors including smoking and alcohol consumption
  • exposure to androgen
  • age >55 years
  • environmental toxin exposure
  • history of coronary artery disease or diabetes mellitus
  • history of STI
  • hot tub use
More risk factors

Diagnostic investigations

1st investigations to order

  • sperm concentration
  • sperm motility
  • sperm morphology
  • seminal fluid parameters
More 1st investigations to order

Investigations to consider

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

Treatment algorithm


obstructive azoospermia

gonadotropin or gonadotropin-releasing hormone deficiencies

primary hypogonadism

high estrogen levels in combination with low testosterone

hyperprolactinemia due to pituitary adenoma

presence of antisperm antibodies

presence of varicocele and no other cause of infertility detected

idiopathic male infertility


medical/surgical intervention ineffective, contraindicated, or unlikely to succeed



Samuel Ohlander, MD

Assistant Professor

Co-Head of the Division of Andrology

University of Illinois




SO declares that he has no competing interests.

Mahmoud Mima, MD

Assistant Professor

Department of Urology

University of Illinois




MM declares that he has no competing interests.

Rodrigo Pagani, MD

Assistant Professor

Co-Head of the Division of Andrology

University of Illinois




RP declares that he has no competing interests.


Dr Samuel Ohlander, Dr Mahmoud Mima, and Dr Rodrigo Pagani would like to gratefully acknowledge Dr Ali A. Dabaja, Dr Ahmad O. Hammoud, and Dr Benjamin Emery, previous contributors to this topic.


AAD, AOH, and BE declare that they have 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.

  • Differentials

    • Cystic fibrosis (CF)
    • Primary hypogonadism
    • Hypopituitarism
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  • Guidelines

    • Guidelines on sexual and reproductive health
    • World Health Organization laboratory manual for the examination and processing of human semen
    More Guidelines
  • Patient leaflets

    Erection problems

    Erection problems: questions to ask your doctor

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