Oxidative Stress in Semen

Abstinence: Avoid ejaculation for 2–5 days before your test. This ensures adequate sample volume and standardised conditions.

Antioxidant supplements: If you're taking antioxidant supplements (vitamin C, E, zinc, selenium, CoQ10, etc.), consider stopping them 1 week before testing if you want a true baseline measurement. Otherwise, the test will reflect your current supplemented state.

Lifestyle: Avoid alcohol, smoking, and excessive exercise for at least 3 days before your test, as these can acutely affect ROS levels.

On the day: When you arrive, you'll be shown to a private room. Wash your hands and genitals with soap and water before producing your sample. Do not use lubricants, saliva, or condoms.

Timing: The sample must be analysed fresh, which is why this test must be performed on-site at the laboratory.

What are reactive oxygen species (ROS)?
ROS are highly reactive molecules (free radicals) produced as a normal byproduct of metabolism. In small amounts, they're necessary for sperm function. However, excessive ROS causes oxidative stress, damaging sperm membranes, impairing motility, and fragmenting DNA.

What is redox potential?
Redox potential (measured by MIOXSYS) reflects the overall balance between oxidants and antioxidants in your semen. A high redox potential indicates oxidative stress—meaning oxidants are overwhelming your body's antioxidant defences.

How does oxidative stress affect fertility?
Oxidative stress can damage sperm cell membranes (reducing motility), cause DNA fragmentation (affecting fertilisation and embryo development), and impair the sperm's ability to penetrate the egg. High ROS is linked to reduced natural conception, increased miscarriage, and lower IVF success.

Can oxidative stress be treated?
Yes. Treatment depends on the underlying cause but typically includes lifestyle modifications (quitting smoking, weight loss, reducing alcohol), treating infections or varicocele, and antioxidant supplementation. Your fertility specialist or GP can recommend an appropriate treatment plan.

Should I stop antioxidants before testing?
If you want a true baseline measurement, stop antioxidant supplements 1 week before testing. If you want to assess your current oxidative status while on supplements, continue taking them as normal.

How long does it take to see improvement?
Sperm take approximately 2–3 months to develop. If you make lifestyle changes or start treatment, repeating the test after 3 months can show whether oxidative stress has reduced.