Semen fertility investigations

The department offers a range of semen infertility investigations which include:

    • sperm concentration (sperm count)
    • sperm motility
    • sperm morphology (normal forms)
    • volume
    • pH
    • viscosity
  • Any other fertility tests should be referred to a specialist andrology unit, e.g. Bristol.
  • As samples must be examined very quickly after production and are complex to process, an appointment system is operated to ensure sufficient time can be allocated to carry out the analysis.
  • Appointments are usually arranged for weekday mornings (Monday to Friday).
  • To book an appointment patients should email or phone the Microbiology Department Appointments voicemail line on 0300 422 4200. Leave a message including full name, date of birth and a contact number and you will be called back.
  • A room is available on site, if required, for patients to use to produce a sample.
  • See also:

Sample requirements


Complete sample collected into a 60 mL wide-mouthed container

Containers are pre-weighed and will be from batches which have been tested for sperm toxicity.

They are sent directly to the patient once an appointment has been made.

Collection Method

An explanatory letter and a patient information leaflet will be sent to patients when they make an appointment

Factors which may affect test results

  • Incorrect container used - not pre-weighed. Volume estimation is performed by weighing the sample. If the weight of the empty container is unknown this will affect the accuracy of the volume estimation.
  • Incorrect container used - not tested for sperm toxicity. Certain brands and batches of containers are toxic to sperm and may affect motility results.
  • Abstinence period. If the patient has not abstained for 48 hours-7 days prior to sample collection, the numbers of sperm detected may be affected.
  • Collection of complete sample. If an incomplete sample is collected, this will affect the volume estimation and may also affect both the numbers of sperm detected and motility results.
  • Delay in sample delivery. If the sample is produced off-site, then it must arrive in the laboratory within 30 (but no later than 50) minutes of collection. Any delay beyond that may affect motility results.
  • Temperature. If the sample is produced off-site, it must be kept warm during transport. An inside pocket, close to the body is recommended. Sample cooling may affect motility results.
  • Use of products during sample production. Any chemicals, for example soap or lubricants may be toxic to sperm and may affect motility results.
  • Other factors including age, weight, nutrition, amount of exercise, psychological stress, recent illness, medication, cigarette smoking, alcohol use, caffeine consumption and environmental or occupational exposure risks may all have an effect on the results of a semen analysis.

Required information

Date and time of sample production

Completion of questionnaire


Patients are advised to keep the sample warm and upright during transport, e.g. in an inside pocket, close to the body

Samples should be transported to the laboratory within 30 (but no later than 50) minutes of collection to arrive between 8.30am and 10.00am

To maintain the standards of our service, we occasionally require fresh samples for quality control and training. We may use any surplus sample for these purposes. Please inform the laboratory on arrival if you do NOT give permission for us to do this with your sample.

Turnaround time

5 days

Note: patients are informed that their results will be available from their G.P. or consultant approximately 7 days after their appointment date

WHO 6th Edition 2021 Clinical Decision Limits:

Volume (ml): 1.4

Concentration: 16 million/ml

Total motility: 42%

Normal forms: 4%

TZI: 1.00-4.00

Ph: >=7.2