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July 25, 2022

Top 5 factors that can affect male fertility

So often, we take fertility for granted until we think about starting a family. But as many people find out, having a baby is not always that simple, and fertility isn't a given.

One-third of infertility cases are due to a female factor, one-third due to a male factor, and one-third are a combination of the two. Research suggests that 60% of male infertility may be due to genetics, and 40% is due to environmental and lifestyle factors.

With this in mind, let's look at the top five factors affecting male fertility.

Male fertility factor #1: Lifestyle

Lifestyle can have a significant impact on male fertility across several different areas. The good news is that, if you improve your lifestyle, you’ll likely be able to improve your fertility as well. Learn more in our Guide to Sperm Improvement.

Diet and male fertility

Your body uses nutrients and energy to produce sperm, which it’s making constantly. Therefore, what you eat can affect sperm quality. Research shows that a diet rich in anti-inflammatory omega-3 fatty acids may improve sperm health, quality, and motility. A diet high in saturated fats may have the opposite effect, and is associated with poorer sperm quality.

You need essential vitamins and minerals such as selenium, zinc, and folate for spermatogenesis (the production and development of sperm). So ensuring your diet includes foods high in these nutrients is essential for fertility.

Foods with high levels of zinc include:

  • Oysters and other seafood
  • Lean red meat
  • Beans and chickpeas
  • Nuts and seeds
  • Fortified whole grains

You can find selenium in foods like:

  • Brazil nuts
  • Fish
  • Meat
  • Poultry
  • Eggs

The following foods are rich sources of folate:

  • Edamame and lentils
  • Green vegetables such as asparagus, broccoli, spinach, and lettuce
  • Citrus fruits
  • Avocado
  • Corn

Eating a diet packed with color — with plenty of fruits and vegetables — is best. However, if you struggle to get all the nutrients you need from your diet, you can always add a male fertility supplement containing essential ingredients to support healthy sperm production.

Cutting down on processed foods and red meat also benefits sperm quality. Studies show that diets in which fish and low-fat dairy products are the primary source of protein are linked with better semen quality.

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Smoking, alcohol, and drug use — how they affect male fertility

An important thing to know about smoking, alcohol, and recreational drugs: these activities can increase free radicals in the body. Free radicals are unstable molecules that can damage cells in your body, contributing to many diseases. Research shows that 25% of men with fertility problems have significant levels of free radicals in their semen.

There is robust research linking smoking and reduced male fertility, and that also includes vaping and heavy, regular cannabis use. All three can affect sperm count, motility, morphology, and genetic health.

You may also need to watch what you drink. While a few drinks per week is unlikely to impair fertility, frequent alcohol consumption and binge drinking may lower your semen parameters, disrupt your balance of male reproductive hormones, or cause other problems like erectile dysfunction.

Exercise and male fertility

As you are probably aware, exercise is good for your physical and mental health in general. Sperm health is no different. Studies show that moderate cardio exercise 3–5 times a week may improve sperm count and quality

Regular exercise also helps with weight management. Research has linked male obesity to decreased pregnancy rates and increased pregnancy loss in couples undergoing fertility treatment. Scientists believe this is because male obesity negatively impacts hormone levels, sperm function, and sperm composition.

Although exercise is positive, you don’t need to become a marathoner to benefit your fertility. In fact, studies suggest that high-intensity exercise such as marathons and endurance training may have a negative effect on sperm health. Biking may also be detrimental to fertility, as it increases heat and pressure on the testes.

Sleep and male fertility

Sleep is another lifestyle factor that may affect your sperm health. Studies link poor sleep quality to reduced sperm motility, lower sperm count, and poor sperm morphology. 

This is because lack of sleep affects your circadian rhythm, increases inflammation in the body, and lowers testosterone levels. To optimize sperm health, 7–8 hours of quality, uninterrupted sleep appears to be the key.

Stress and male fertility

The link between stress and infertility is still unclear. But several studies point to a connection between high levels of anxiety and stress and low sperm concentration, low sperm count, and reduced motility. 

It's normal to experience a whole range of emotions if you are embarking on fertility treatments. And, it's important to consider the fact that infertility and fertility treatments may cause stress, contributing to the correlation between the two.

Stress can also impact other areas of your life, leading to poor sleep, poor diet, lack of exercise, and increased smoking and alcohol use. As we've mentioned, many of these lifestyle factors can negatively impact male fertility.

Reducing your stress levels is a good idea on your family-building journey, but it can be challenging. If trying to reduce stress on your own is not working, consider reaching out to a counselor or support group.

Male fertility factor #2: Genetics

Genetic or congenital infertility is due to a condition that’s present at birth, due to your specific DNA. Several rare genetic conditions can cause male infertility, including:

Having a genetic condition does not necessarily mean that you can't have children, but it may mean that you need to explore fertility treatment options. If you are considering starting a family and have one of these genetic conditions, speak to a fertility specialist for advice and support.

Male fertility factor #3: An issue with the vas deferens

The vas deferens is part of the internal male reproductive system. These ducts transport sperm from the testes and out of the body during ejaculation, so they are pretty essential to male fertility. 

Blockages can occur in the vas deferens due to:

  • Vasitis, inflammation and swelling of the vas deferens
  • Infection
  • Spermatocele, a type of cyst that develops above or behind your testicle
  • Testicular cancer 
  • Trauma to the testicle area

Although rare, some men have congenital absence of vas deferens (CAVD), which means they are born without one or both tubes. This is particularly common in men with cystic fibrosis, as upwards of 95% of men with cystic fibrosis have CAVD. 

Depending on the cause of the vas deferens problem, several treatment options are available to assist with fertility and conception.

Male fertility factor #4: Varicocele

A varicocele is an enlargement of the veins within the scrotum. Varicocele is relatively common. Research identifies that varicocele is present in 15% of healthy men and up to 35% of men with primary infertility. It can occur on either or both sides of the scrotum, but for some reason it’s more common on the left.

In the scrotum veins, there are valves that regulate blood flow to and from the testicles. If these valves become defective, the blood backs up, causing the veins to enlarge (a varicocele). Varicocele is associated with decreased semen parameters, likely because it increases the temperature in the scrotum.

Varicocele can happen during puberty, when the testicles grow rapidly and require more blood. Often, people don't realize they have a varicocele as often there are no symptoms. On occasion, those with varicocele may experience a dull ache or discomfort in the testicles (especially in hot weather).

A varicocele doesn't always cause infertility. Two-thirds of men with a varicocele do not have fertility problems. If a varicocele is thought to be contributing to infertility, a surgeon can block the affected vein to redirect the blood flow toward the unaffected veins. Varicocele repair surgery may help improve sperm parameters and increase rates of pregnancy

Male fertility factor #5: Hormone imbalance

There are a few different hormones that all play their part in male fertility:

  • Testosterone, essential for the development of the male sex organs, sex characteristics, and spermatogenesis
  • Follicle-stimulating hormone (FSH), key to spermatogenesis
  • Luteinizing hormone (LH), responsible for testosterone production in the testes
  • Estrogen, which can reduce sex drive and decrease sperm concentration and motility if levels are too high
  • Prolactin, linked to reduced semen quality if levels are too high
  • Thyroid-stimulating hormone (TSH), which can cause problems with the thyroid if too low or too high, which in turn may impact fertility

An imbalance in hormones, especially testosterone, FSH, and LH, can negatively impact sperm count, concentration, morphology, and motility. It's not always easy to know if your hormones are out of balance, but some tell-tale signs are:

  • Hair loss
  • Weight gain or loss
  • Low sex drive
  • Erectile dysfunction
  • Fatigue or a lack of energy and enthusiasm 
  • Depression and anxiety
  • Difficulty sleeping
  • Irritability
  • Loss of lean muscle mass

If you suspect that hormones may be causing fertility problems, then speak to your health care provider or fertility specialist. They can carry out several tests to determine your hormone levels and assess your fertility. Learn more about hormone testing for infertility.

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If you want to understand what’s affecting your fertility, a semen analysis test is a good starting point. This analysis assesses sperm count, concentration, motility, and morphology to help you understand and optimize your fertility. Legacy’s at-home semen analysis also includes personalized recommendations for improving your fertility, based on lifestyle factors. Get started.

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