What is the difference between azoospermia & oligospermia?

What is the difference between azoospermia and oligospermia?

Oligospermia and azoospermia are words that can be used a lot in the world of male fertility. However, for many these words won’t mean anything. In simple terms oligospermia is means that there is ‘not a lot of sperm’ whereas azoospermia means there is ‘no sperm’. Like many words that are used in the medical word, oligospermia and azoospermia have a Greek origin.

The scientific terms for both oligospermia and azoospermia are:


‘Oligospermia is a condition where the number of sperms required in a male’s ejaculate to conceive is less than the minimum level for conception. This condition is also called oligospermia. The cut off value, according to WHO is 20 million sperm per millilitre, any sperm count less than this value is labelled as oligospermia. It is the most common cause of decreased chances of conception and infertility in men.’


‘Azoospermia is a medical condition where there is a complete absence of sperm in the semen sample. At least two semen samples should be studied before diagnosing a male with azoospermia, due to fluctuations between samples. It affects about 1% of male population and accounts for 20% of male infertility cases.’

Both oligospermia and azoospermia can be brought on by a number of different causes. These can include:

  • Hormone imbalance
  • Infection
  • Varicocele
  • Blockage
  • High testicular temperature
  • Sexually transmitted infections/diseases
  • Cancer

Please note these are just some of many causes.

It is important that if you are struggling with fertility, the male partner should have a sperm test to check their fertility levels. If a condition such as oligospermia or azoospermia is found, further tests can be done to find a cause and tailor a treatment plan to help your individual needs.

If you would like to speak to our team about oligospermia and azoospermia please contact us on 01753 891118 to book an appointment at one of our locations.

This article is intended to inform and give insight but not treat, diagnose or replace the advice of a doctor. Always seek medical advice with any questions regarding a medical condition.

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