Oligospermia (Low Sperm Count)

What is oligospermia?

Oligospermia, or low sperm count, means there are fewer sperm in the semen than expected. Under the WHO 2021 reference values, a sperm concentration below 16 million per millilitre, or a total count below 39 million per ejaculate, is considered low. It is often described as mild, moderate or severe; a concentration below 5 million per millilitre is usually called severe oligospermia. A low count reduces the chance of natural conception but does not mean pregnancy is impossible.

Symptoms and signs

Most men feel completely well and the problem is found only on a semen analysis. Occasionally there are clues such as:

• Difficulty conceiving after 12 months of regular unprotected intercourse
• Low sex drive or erection problems
• Pain, swelling or a lump in the scrotum, such as a varicocele
• Reduced facial or body hair, suggesting a hormone problem

Causes and risk factors

• Varicocele (enlarged veins in the scrotum)
• Hormonal problems, including low FSH and LH, high prolactin or thyroid disorders
• Genetic causes such as Y chromosome microdeletions or Klinefelter syndrome, especially when counts are very low
• Past undescended testes, mumps orchitis, testicular injury or infection
• Use of testosterone, anabolic steroids or some medicines
• Smoking, heavy alcohol use, obesity and recreational drugs
• Heat exposure, such as long hours in hot workplaces or laptops on the lap
• Recent fever or illness, which can lower counts temporarily

How it is diagnosed

• Semen analysis after 2 to 7 days of abstinence; an abnormal result is usually repeated, as counts vary
• Physical examination of the testes and scrotum
• Hormone tests: FSH, LH, testosterone and prolactin
• Scrotal ultrasound if a varicocele or other problem is suspected
• Karyotype and Y chromosome microdeletion tests for severe oligospermia
• Sperm DNA fragmentation testing in selected cases

Treatment options

Lifestyle and medicines

Stopping smoking, limiting alcohol, losing excess weight and avoiding heat can help. New sperm take around 2 to 3 months to develop, so improvements show only after this time. Men using testosterone are advised to stop under supervision. Hormone treatment helps when a specific deficiency is found. Antioxidant supplements are widely used, but evidence for improving pregnancy rates is mixed.

Varicocele repair

Surgery or embolisation may be advised for a varicocele that can be felt on examination when the semen analysis is abnormal.

IUI

In mild oligospermia, sperm are washed and concentrated and placed directly into the uterus around ovulation. This works best when enough motile sperm remain after preparation.

IVF with ICSI

For moderate to severe oligospermia, or when IUI has not worked, IVF with ICSI is recommended. A single sperm is injected into each egg, so only a small number of healthy sperm are needed.

Chances of pregnancy

Many couples affected by low sperm count conceive, with or without treatment. The chance depends on how low the count is, sperm motility and shape, the cause, and especially the female partner's age and ovarian reserve. Your specialist will explain realistic chances based on both partners' results, but no treatment can guarantee pregnancy.

When to see a fertility specialist

See a specialist if a semen analysis shows a low count, if you have tried for 12 months, or sooner if your partner is 35 or older. Both partners should be tested together. Iswarya Fertility offers semen analysis and male fertility care at its 91+ centres.