Friday, February 27, 2009

Absence of the vas deferens

The vas deferens is the muscular tube that transports sperm from the testicle to the urethra and ultimately to its target destination.  Most have have 2 of them, one for on the right and one on the left side.  But some men have only one vas and some are missing both.  This condition is known as congenital absence of the vas deferens.  It is uncommon, but I see 2 cases per year, at least, in my busy male infertility practice.

Most men with only one absent vas never know what they are missing.  They are fertile.  In these men, the discovery is made when the man goes to the urologist for a physical exam, say before a vasectomy.
Men with 2 missing vasa (plural of vas), are infertile.  Actually, this is not true.  They are very fertile, only the sperm cannot get out of the epididymis and testicle.  In order for these men to impregnate a partner, they sperm must be retrieved surgically.   This can be done quite easily, in about 5 minutes actually, and that terrifically healthy sperm can then be used with IVF or ICSI.  This sperm retrieval procedure is called "a sperm retrieval." 

The sperm can be harvested from either the epidiymis or testicle or both.  The procedure can be done in the office, underl local anesthetic, with a very skinny needle, and is successful ~99% of the time. 

About 10% of men with a missing vas deferens will have a missing kidney as well.  This happens because the kidney, ureter, and vas deferens all form at the same time in-utero--or when the baby is in the womb--and all come from something called the wolfian duct.  No patient would ever need to know this, but I find it interesting.  When I diagnose a man with a missing vas deferens, I order a renal sonogram.  People like to know if they have one or two kidneys.

That's it..