Condition & Treatments
/ Vasal aplasia (CBAVD)
Born without the vas deferens? Your own biological child is still very possible.
Vasal aplasia means the tubes that carry sperm from the testes (the vas deferens) did not form. When both are missing, it is called congenital bilateral absence of the vas deferens (CBAVD). The testes usually make sperm normally, so sperm can almost always be collected for IVF/ICSI
I N S H O R T
CBAVD causes no sperm in the semen, with a low semen volume and acidic pH.
It is closely linked to the cystic fibrosis gene (CFTR), even in men who are otherwise healthy.
Your partner should be tested too, before any treatment, to understand the risk for your child.
How it is diagnosed
Examination: the vas deferens cannot be felt in the scrotum.
Semen analysis: no sperm, low volume and low pH.
Scrotal and transrectal ultrasound, to check the epididymis, testes and seminal vesicles.
Kidney ultrasound, because a missing vas on one side can come with a missing kidney
Genetic tests: CFTR testing for you, and for your partner.
Treatment options
Sperm retrieval: percutaneous epididymal sperm aspiration (PESA) or testicular sperm aspiration (TESA), under sedation, as a day case.
Microsurgical epididymal sperm aspiration (MESA), when larger numbers of sperm are wanted for freezing.
IVF/ICSI with the retrieved sperm, fresh or frozen.
Genetic counselling and embryo testing (PGT), if both partners carry a CFTR change.
Why this matters to your care
The surgery itself is usually straightforward. What matters is getting the genetics right for your future child, and timing retrieval with your IVF clinic. Prof Raheem co-ordinates both.
Common questions
Will sperm be found?
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In almost every man with CBAVD, because sperm production is usually normal.
Does this mean I have cystic fibrosis?
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Usually not. Most men carry a CFTR change without the lung or gut disease.
Can the vas be reconstructed?
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No. The tubes are missing, not blocked, so sperm retrieval with IVF/ICSI is the route to a pregnancy.
Prof Raheem's published work on this topic
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Genetic causes of male infertility (book chapter). Male Infertility in Reproductive Medicine. CRC Press, 2019.