Oligospermia (Low Sperm Count): Causes, Testing and Management in the UK

Oligospermia refers to a condition where a man has a lower than normal sperm count in his ejaculated semen. According to the World Health Organization (WHO) and NHS guidance, a healthy sperm count is typically 15 million sperm per millilitre of semen or higher. If your results fall below this threshold, it is classified as oligospermia.

Fertility is a journey many couples undertake, and in approximately half of all cases where conception is difficult, a 'male factor' is involved. Oligospermia does not mean conception is impossible; rather, it suggests that the chances of a sperm reaching and fertilising an egg are statistically lower. Understanding the root cause is essential for determining the best treatment or lifestyle adjustments needed to improve fertility outcomes.

There are a variety of medical, environmental, and lifestyle factors that can contribute to a reduced sperm count. These are generally categorised into three main areas:

Medical Causes

• Varicocele: A swelling of the veins that drain the testicle, which can increase the temperature and affect sperm production.
• Hormonal Imbalances: Issues with the hypothalamus, pituitary gland, or the testicles themselves can lead to low testosterone or inadequate sperm stimulation.
• Infections: Some infections, such as those caused by sexually transmitted infections (STIs) like chlamydia or gonorrhoea, can interfere with sperm production or cause scarring.
• Ejaculation Issues: Conditions like retrograde ejaculation can prevent sperm from leaving the body correctly.

Lifestyle and Environmental Factors

External factors play a significant role in male fertility. Excessive alcohol consumption, smoking, and the use of anabolic steroids are well-documented triggers for oligospermia. Additionally, prolonged exposure to heat—such as frequent use of hot tubs, saunas, or wearing tight underwear—can temporarily lower sperm counts by overheating the scrotum.

For many men, the only sign of oligospermia is the inability to conceive after 12 months of regular, unprotected intercourse. However, if the low sperm count is caused by an underlying issue, such as a hormone deficiency or a chromosomal abnormality, you might notice:

• Reduced erectile function or low libido.
• Pain, swelling, or a lump in the testicular area.
• Decreased facial or body hair.

Diagnosis in the UK typically involves a semen analysis. This test examines the quantity, movement (motility), and shape (morphology) of your sperm. Because sperm counts can fluctuate, UK doctors usually recommend two separate tests, often 12 weeks apart, to get an accurate average of your fertility profile.

The process of sperm production (spermatogenesis) takes roughly 75 to 90 days. This means that lifestyle changes you make today will not be reflected in your sperm count for about three months. Evidence-based recommendations aligned with NICE clinical knowledge summaries include:

• Weight Management: Maintaining a healthy Body Mass Index (BMI) helps regulate hormones.
• Smoking Cessation: Smoking is linked to lower sperm quality and count.
• Dietary Adjustments: A diet rich in antioxidants, zinc, and selenium supports healthy sperm development.
• Avoiding Heat: Swapping tight briefs for loose boxers and avoiding hot baths can keep scrotal temperatures at the optimal level for sperm survival.

If lifestyle modifications are insufficient, medical interventions may be necessary. For those with hormonal deficiencies, hormone replacement therapy may be prescribed. Antibiotics can clear underlying infections that may be affecting sperm health. In cases of physical obstruction or varicocele, minor surgical procedures are sometimes recommended by a urologist.

If natural conception remains difficult, assisted reproductive technologies (ART) such as Intro-Cytoplasmic Sperm Injection (ICSI) or IVF are highly effective for men with oligospermia. ICSI involves injecting a single healthy sperm directly into an egg, bypasssing the need for a high sperm count.

Many men find discussing fertility concerns in person to be a daunting experience. If you have been trying for a baby for over a year without success—or sooner if you have risk factors like a history of undescended testicles—you can speak to a GP online in the UK for a confidential consultation.

An online doctor can review your medical history, discuss your lifestyle, and explain the steps for arranging a semen analysis. They can also provide a referral for further specialist testing if needed. Accessing support early is key to managing anxiety and building a clear roadmap toward fatherhood. Our service offers a discreet way to get the evidence-based advice you need from the comfort of your home.