Skip to main content


TDL’s Andrology division focuses on the single most important factor determining a man’s fertility potential – the production of healthy sperm.

A semen analysis, which provides information about sperm count, motility and morphology, has classically been used as the marker of male fertility potential. However, there are other parameters given in a semen analysis that are often neglected or overlooked; these may indicate important pathologies, such as infection, prostatic disease, immunological infertility, retrograde ejaculation, malformation or obstruction of the genital tract, tumour, and congenital or endocrine disorders.

Early diagnosis of the male factor is important in order to detect any underlying pathology, to determine the extent of infertility, and to ensure appropriate treatment. It may also avoid unnecessary investigations for the female partner, particularly if her age is a limiting factor.

For men who have had a vasectomy, clearance should only be given when there is no evidence of presence of sperm in two consecutive semen samples. It is therefore vital to ensure that results are reported according to best practice guidelines. Special clearance may be given at the doctor’s discretion when there are persistent non-motile sperm present.


Guidelines for Producing Samples

Ideally semen samples should be produced on-site at TDL’s Patient Reception at 76 Wimpole Street, London. Patients should abstain from ejaculation for 2–3 days before the test (but no less than 2 days and no longer than 5 days). This requirement is important for semen analyses and post-vasectomy analyses to ensure reliability of results. It is possible that samples that do not comply with guidelines for abstinence and collection may not be able to be processed. All semen samples must be produced directly into the sterile containers provided by TDL.

All containers are weighed and batch tested for sperm cytotoxicity. In exceptional circumstances when semen samples are produced off-site, they can only be accepted by the Andrology Department in sample containers provided by TDL.

WHO 2010 guidelines state that two semen analyses should be performed before any diagnosis is confirmed. This may require requests for two (separate) semen analyses.

All semen samples must be accompanied by a completed 'Information Form For Patients Producing Semen Samples'.

Download: Information Form For Patients Producing Semen Samples

Download: Semen sample collection instructions



It is important to make an appointment for all semen samples (on or off site), whether for a comprehensive semen analysis or for post-vasectomy analysis.

It may be necessary to give patients who attend without an appointment a specific time to re-attend. The first appointments for post-vasectomy samples should usually be 12 weeks and 20 ejaculations after surgery.

Appointments can be made by calling 020 7025 7940. There is an attendance fee of £50.00 in addition to pathology charges.

Please complete a Pathology Request Form for your patient. If you would like to request other pathology, you can use the same form or complete a second additional form. Results will usually be reported to you within 48 hours.

If you would like to discuss these tests, or any aspect of this service, please contact TDL Andrology on 020 7025 7940 or email andrology for further information.

Book an appointment online

TDL Update: Andrology reference values

Andrology: Pathology and Services

Routine tests, and tests by special arrangement.

Sperm DNA fragmentation

High sperm DNA fragmentation is associated with reduced natural pregnancy rates and assisted conception pregnancy rates as well as live birth rates.

Sperm anueploidy

Sperm with a high rate of aneuploidy have a negative impact on pregnancy rate and are associated with recurrent pregnancy loss.

Oxidative Stress in Semen

There is growing evidence to support a link between oxidative stress and male infertility.

Lead consultant

Professor Sheryl Homa