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Post Vasectomy Semen Analysis Service

Cellular Pathology

Principle of Examination

Vasectomy is a safe and effective method of contraception for men. Post vasectomy semen analysis (PVSA) is recommended to confirm clearance of stored spermatozoa and also to identify rare cases of early recanalization or technical failure. Sterility is usually confirmed after a single post vasectomy seminal fluid is clear of spermatozoa. However if spermatozoa are present a second sample must be provided to the lab within 1 hour of production to assess motility. If sperm are present in the second sample a third sample may be recommended which will be sent to a suitable clinic specialising in reproductive medicine.

Sperm motility will be reported in specimens received within 4 hours of sample production, where motile or non-motile spermatozoa are identified in the initial sample preparation.

Spermatozoa motility will not be reported by the laboratory if spermatozoa are only identified in the centrifugate preparation. This is due to the centrifugation process, which may result in previously motile spermatozoa being rendered non-motile. In these instances  the report will state ‘spermatozoa present’ with no comment on motility. It is recommended that these patients provide a second sample to the laboratory within 1 hour of production to assess motility.

For EASTERN service users, see HERE

For NORTHERN service users, see HERE


Interpretation & Advisory Service for PVSA

For further advice and result interpretation please contact:

Dr Richard Wise and Dr Claire Tomlinson (MBChB, MRCGP, DRCOG, GPxSI (vasectomy), Trainers in Vasectomy under LA) at St Thomas Health Centre, Exeter on 01392 676676.


Specimen Requirements

PVSA samples can either be requested via GPOCS or using a request form.

  • Patients are usually asked to provide a post vasectomy sample, a minimum of 12 weeks after surgery and after a minimum of 20 ejaculations.  A second sample may be required for persistent spermatozoa and may be sent to a clinic specialising in reproductive medicine for full analysis.
  • The laboratory will supply the practitioner (or patient) with a 50ml toxicity tested specimen container, a carrying box and a request form. To obtain these kits please contact Pathology Stores on 01392 402906.
  • A toxicity tested specimen container MUST be used.
  • The entire seminal fluid sample must be collected.


Specimen Labelling Procedure
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