Skip to content
Home » Andrology » Sperm retrieval & ART

Sperm retrieval & ART

Spermatogenesis in the testis is often focal and random – found in small areas and not throughout the whole testis.

Methods of sperm retrieval for non obstructive azoospermia:

  1. Fine needle aspiration mapping (requires subsequent second therapeutic procedure)
  2. TESA (testicular sperm aspiration)

Office based, retrieval with biopsy needle – retrieval rates 11 – 60 %

  1. Conventional TESE

Scrotal incision and open biopsy of the testis. Retrieval rates about 50 %.

  1. Micro TESE (mTESE)

Operative microscope 20 – 25 x – identifying seminiferous tubules which are largest, most dilated and opaque, and therefore more likely to harbour sperm.

 

mTESE thought to increase likelihood of sperm retrieval with smaller amount of tissue removed and theoretically therefore less complications.

Reduction of testosterone levels is seen with both cTESE and mTESE, with less effect with mTESE.

MicroTESE recommended in both AUA and EAU guidelines for non obstructive azoospermia.

 

For obstructive azoospermia sperm can be extracted or aspirated from either the testis (TESE, mTESE, TESA) or epididymis (microscopic epididymal sperm aspiration MESA, percutaneous epididymal sperm aspiration PESA)

 

For retrograde ejaculation

Trial of alpha agonists, alkalinisation of urine then collection of post ejaculatory urine (or catheterisation), or surgical extraction i.e. TESE, TESA, PESA.

 

For anejaculation

Trial of penile vibratory stimulation or rectal electroejaculation (may only induce emission and contents still need to be collected, may go retrograde).

Surgical extraction i.e. TESE, TESA, PESA.

 

Practical tips:

  • Testicular blood supply inserts posteriorly under the epididymis – subtunical vessels then run under albuginea and are end arteries supplying areas of testis
    • Therefore needle aspiration or core biopsies should be introduced from anterior and directed anteromedial or anterolateral
  • PESA involves blindly putting needle into epididymis – testicular artery enters testis underneath head and body of epididymis, and risk of injuring it
  • MESA provides excellent sperm retrieval rates for obstructive azoospermia
    • Deliver testis through scrotal incision – dilated tubules usually easily evident and can be punctured, defects closed with bipolar
  • mTESE gold standard for non obstructive azoospermia:
    • Equatorial incision of tunica albuginea with microknife
    • Gentle bivalving and haemostasis of any bleeding with bipolar
    • Retrieval of most promising tubules – largest diameter, white/opaque
    • Sparing of centrifugal vessels
    • Essential to have well trained scientist/technician on hand to identify sperm – which ends the procedure

 

Methods of ART

Intrauterine insemination (IUI)

  • Small catheter placed through cervical os and sperm directly placed into uterus.
  • Controls variables related to initial journey of sperm – overcoming penile/urethral, vault and cervical barriers
  • Must have normal Fallopian tube(s). Generally women < 40. Cheaper than IVF.

 

In vitro fertilisation (IVF)

  • Ovarian hyperstimulation with ova harvested prior to ovulation.
  • Recovered oocytes mixed with processed semen in a Petri dish with male gamete fertilising oocyte somewhat naturally.
  • Developing embryos incubated for 2-3 days in culture, then placed in uterus trans-cervically.
  • 20 – 30 % of transferred embryos result in clinical pregnancies.

 

Intracytoplasmic sperm injection (ICSI)

  • Single sperm injected directly into an egg using glass micropipette.
  • Therefore oocyte can be fertilised independently of the morphology and motility of the sperm -> procedure of choice for male factor infertility.

 

Antisperm antibiodies

Disruption of the blood-testis barrier (Sertoli cell tight junctions) exposes the immunologically protected spermatids and spermatozoa to antibody formation.

Antisperm antibodies may cause sperm agglutination, impeded sperm motility and reduced fertilisation potential.

Conditions associated with antisperm antibody formation include:

  • Vasectomy
  • Testis trauma
  • Torsion
  • Orchitis
  • Cryptorchidism
  • Testis cancer
  • Varicocele

 

Antisperm antibodies can be tested for directly (sperm surface immunoglobulins) or indirectly (plasma or serum).

  • Direct assays preferred for clinical relevance.

High levels of antisperm antibodies are seen after vasectomy, but the clinical relevance is unclear.

AUA guideline recommends against routine testing for anti-sperm antibodies as it doesn’t change management.