PESA (percutaneous epididymal sperm aspiration)

What PESA involves

The UK fertility regulator, the HFEA, lists “Percutaneous epididymal sperm aspiration (PESA)” first among five ways of collecting sperm surgically. It says “PESA and TESA involve a fine syringe being inserted into either the epididymis or the testicle to extract the sperm. It's a quick and relatively painless procedure that's usually performed under local anaesthetic.”

A microsurgical version of the same idea is MESA, which the HFEA describes as “examining the epididymis under an operating microscope and taking fluid samples for further examination to see if there are any sperm.” It notes that “MESA and MicroTESE are both performed under general anaesthetic.” Collection from the testicle itself is covered on the TESA and micro-TESE pages.

When it is used

PESA is a treatment for a blockage rather than for a lack of sperm production. The HFEA says “You may have PESA, MESA, TESA or TESE if you have no sperm in your semen due to a blockage (obstructive azoospermia).” It gives as examples “you've had a vasectomy” and “you've had a sexually transmitted infection like chlamydia.”

On why some men have no sperm in their semen, it says “Often it's due to genetics, but it can also occur as a result of a sexually transmitted infection or certain medical treatments.” Whether it is appropriate in a particular case is a clinical decision for the treating doctor. This directory does not make that judgement.

What the regulator says about risks

On side effects, the HFEA states: “Side effects tend to be rare, but bleeding and infection can occur.” It adds: “A small number of men experience a drop in their testosterone following surgical sperm retrieval, which may cause problems with sexual function, sleep, muscle weakness and anxiety.”

It is also clear that retrieval is not the end point: “Successfully extracting sperm doesn't guarantee you'll have a baby.” and “You'll need to have a fertility treatment like ICSI to use your sperm.” See ICSI.

Questions

Who might have PESA?

The HFEA says men who “have no sperm in your semen due to a blockage (obstructive azoospermia).”

Is it painful?

The HFEA describes PESA and TESA as “a quick and relatively painless procedure that's usually performed under local anaesthetic.”

Sources

• HFEA, Surgical sperm extraction, read 25 September 2026.
• The Assisted Reproductive Technology (Regulation) Rules, 2022, G.S.R. 419(E), 7 June 2022, para 10.1 (not changed by the Amendment Rules, 2026, G.S.R. 491(E)), read 25 September 2026.
• Clinic data: each clinic's own website, as read by this directory; registry level from the National ART & Surrogacy Registry extract.