Unlocking the Truth: Does Testosterone Affect Sperm? Discover Now!

Published February 16, 2024 | By zeke

Testosterone is an important hormone that plays a key role in several bodily functions for both men and women. Even though it’s often thought of as the “male” hormone, testosterone is produced in women’s bodies, too, just at lower levels. This important hormone plays a role in several systems in the body.
In men, testosterone is produced mainly in the testicles and regulated by the hypothalamus and pituitary gland in the brain (1). It promotes the development of secondary sex characteristics like facial hair growth and a deeper voice. Testosterone also helps maintain muscle mass and strength, bone density, red blood cell production, mood, and sex drive (2).
In terms of reproduction, testosterone signals the testicles to produce sperm. It works together with another hormone, follicle-stimulating hormone (FSH), to kickstart and maintain spermatogenesis – the creation of new sperm cells (3). Sperm cells need testosterone to properly mature and develop the ability to swim and fertilize an egg (4). Men with very low testosterone often have impaired spermatogenesis and reduced fertility (5). On the other hand, men with abnormally very high testosterone levels can also disrupt spermatogenesis and cause infertility [6]. Overall, testosterone is essential for optimal sperm production and male fertility, but levels must be maintained within a normal range.

Advantages and Disadvantages of Good Fertility

Here are some Pros and Cons of having good fertility:

Advantages:

Improved ability to conceive children naturally
The wider window of opportunity for conception
Less need for fertility treatments like IVF
Potentially lower stress around conception
Confidence in reproductive health

Disadvantages:

Higher likelihood of unplanned pregnancy
Need for more vigilant birth control use.
Potential for a greater number of children than desired
Possibility of conceiving later in life when less desirable

Does Testosterone Affect Sperm?

Yes, testosterone affects sperm; this is due to the fact that testosterone is essential throughout multiple stages of sperm development and function. Here are some of the ways that testosterone levels and activity affect sperm:

Sperm Production

As discussed, testosterone is essential for spermatogenesis – the process of sperm production and maturation. FSH and LH from the pituitary gland stimulate the testes to produce testosterone, which then promotes mitosis and meiosis of germ cells to form mature sperm [7]. Men with low testosterone, such as in hypogonadism, frequently have impaired spermatogenesis and low sperm counts.

Sperm Quality

Adequate testosterone levels are necessary to support the genomic integrity of sperm. Testosterone may impact sperm health by influencing apoptosis and reactive oxygen species (ROS) that can cause DNA fragmentation and impact sperm viability [8]. Men with low testosterone have higher proportions of sperm with DNA damage compared to fertile men.

Sperm Motility

Testosterone promotes sperm motility by enhancing mitochondrial activity and ATP production in sperm, providing energy needed for movement. It also increases intracellular calcium and cAMP signaling pathways vital for sperm motility. Low testosterone reduces hyperactivation and motility of sperm due to these impaired signaling pathways.
Sperm Maturation
As sperm move through the epididymis, testosterone induces biochemical and physiological changes essential for them to gain motility and become functionally mature. Disruption of testosterone inhibits the maturation process, keeping sperm in an immature, non-functional state.

Low Testosterone (Low T)

Low testosterone, also known as hypogonadism or “low T,” refers to an abnormally low level of the testosterone hormone in the body.

Effects of Low Testosterone

Having chronically low testosterone can lead to various unpleasant effects and health issues:

Low libido and erectile dysfunction.
Loss of muscle mass and strength.
Increased body fat and obesity.
Loss of facial, body, and pubic hair.
Fatigue, poor concentration, and depression.
Reduced bone mineral density, osteoporosis risk.
Metabolic syndrome, Type 2 diabetes.
Cardiovascular problems

Who is Affected by Low T?

Several groups are commonly affected by low testosterone (low T):

Aging men: Testosterone levels begin declining after age 30 and drop more significantly after 50. Up to 39% of men over age 45 may have low T [9].
Men with chronic illnesses: Conditions like type 2 diabetes, obesity, metabolic syndrome, HIV/AIDS, and chronic liver or kidney disease increase the risk of low T [10].
Men taking certain medications: Long-term use of opioids, steroids, certain antifungals, and anticonvulsants can impair testosterone production [11].
Men with pituitary or testes disorders: Tumors, infections, injury, or other disorders in the pituitary gland or testicles compromise the organs’ ability to produce testosterone [12].
Obese men: Higher levels of the aromatase enzyme in fatty tissues convert testosterone to estrogen, resulting in diminished testosterone [13].

Prevalence of low T

Low T primarily affects middle-aged and older men, though it can occur at any age. According to research, around 4-5 million men in the United States have low testosterone. [14] This figure rises to close to 20% of men over age 60. Globally, a study estimates that around 6% of men worldwide suffer from low T, which equates to over 20 million men. [15]

Other Things That Lower Testosterone and Sperm Count

Radiation and chemotherapy – Cancer treatments like radiation to the testes and some chemo drugs damage the testes and lower testosterone and sperm count.
Testicular overheating – Frequent hot tub use, tight underwear, placing laptops on the lap, etc., can overheat the testes and impair sperm production and testosterone.
Stress and lack of sleep – Prolonged stress and sleep deprivation negatively impact reproductive hormone balance.
Poor diet – Deficiencies in zinc, vitamin D, vitamin C, and other micronutrients can reduce testosterone levels and sperm health.
Excess alcohol – Chronic heavy drinking is toxic to the testes, lowering testosterone. Alcohol use also reduces sperm production.
Smoking – Contains toxic chemicals like cadmium that damage sperm. Smoking may also lower testosterone levels

Does Testosterone Increase Sperm Count?

Yes, testosterone does play an important role in regulating sperm production and increasing sperm count [16].
As previously discussed, testosterone is an important hormone for male fertility and reproduction. It plays a crucial role in spermatogenesis – the process of producing mature sperm cells. Here’s a more detailed look at the connection between testosterone and sperm count:
To begin, testosterone signals the testes to produce more sperm. It binds to receptors in cells within the testes called Sertoli cells. When activated by testosterone, these Sertoli cells nurture developing sperm cells through the various stages of maturation. The more testosterone there is, the harder the Sertoli cells work to produce sperm.
In addition, adequate testosterone levels prevent sperm cell death and damage. Testosterone provides essential proteins that help sperm survive as they develop and mature. It also regulates the survival of mature sperm that have completed spermatogenesis and are stored in the epididymis.
Furthermore, testosterone is needed for the proper functioning of accessory sex glands like the prostate and seminal vesicles. These glands produce fluids that protect sperm as it travels through the male reproductive system and out of the penis during ejaculation. So, healthy testosterone activity promotes the production of these helpful fluids.
Clinical research reflects these biological mechanisms. Studies consistently show that men with higher testosterone levels tend to have higher sperm counts on semen analyses. And men with abnormally low testosterone are more likely to have lower sperm production and quality.
However, note that artificially elevated testosterone levels induced by anabolic steroid abuse or testosterone supplements can actually impair spermatogenesis and reduce sperm counts. In fact, a study looking at sperm production in men taking testosterone supplements found that the vast majority (over 88%) of those taking testosterone without a medical requirement were found to have no sperm cells present in their semen (17).
This effect is likely due to testosterone being aromatized into estrogen, which inhibits the hormonal signals needed for sperm maturation.
So, while moderate levels of testosterone are important for supporting healthy sperm production, more testosterone does not necessarily mean higher sperm counts. The relationship follows more of an inverted U-shaped curve, where too little or too much testosterone can reduce sperm count.

What Raises Testosterone and Ultimately Results in a Higher Sperm Count?

There are some natural ways men can potentially raise testosterone levels and improve sperm count and quality:

Strength training and weight lifting: Resistance training can stimulate testosterone production and may improve sperm parameters like count and motility. Aim for at least 2 sessions per week.
Lose excess weight: Being overweight or obese is associated with lower testosterone. Losing excess fat, especially around the belly, may help increase testosterone.
Have sex: Frequent ejaculation does not reduce sperm count or fertility. Regularly clearing out weak sperm improves sperm quality. So, there’s no need to limit sexual activity to “save” sperm.
Limit alcohol: Excessive alcohol intake is linked to lower sperm count and quality. Heavy drinking impacts sperm shape and ability to fertilize while depleting nutrients needed for sperm generation. For optimal fertility, men should limit alcohol consumption to 1-2 occasional drinks (18).
Supplements: Getting adequate folic acid and zinc may help improve low sperm count. A 2002 study found that men taking folic acid and zinc supplements experienced a significant improvement in sperm count – around a 74% increase, on average, compared to men not taking the supplements (19).
Testosterone Therapy: Testosterone replacement therapy (TRT) under medical supervision may be the most effective option to restore sperm production to normal levels. Lifestyle and vitamin supplements can help, but TRT is proven to directly target the root hormonal cause of low sperm counts in aging males. Consult a doctor to determine if TRT is appropriate.