There are countless facts regarding sperm, the male reproductive cells. For this reason, it can be hard to split truth from myth.
Although many people have some knowledge about sperm, many misconceptions about the male gamete also exist. This article will separate some interesting sperm facts from some common myths.
The following are four confirmed sperm-related facts:
Sperm and semen are not the same
Sperm cells are male gametes. These cells’ function is to find a female gamete with which to fuse, for non-assisted reproduction to occur. In this process, sperm enters the vagina by being expelled through the penis. This expulsion is known as ejaculation.
When this occurs, the sperm arrives within a fluid created by the male sex organs. This mixture of sperm and fluid is called semen.
Sperm takes a long time to produce
The process of producing sperm is known as spermatogenesis.
Testicles, the male reproductive organs, produce sperm. Inside the testicles are small tubes called seminiferous tubules.
Spermatogenesis involves several stages:
- Hormones enter the tubules that house germ cells.
- With the help of these hormones, such as testosterone, the germ cells divide and change several times.
- They gradually turn into spermatids, which are young sperm cells.
- These grow and mature into spermatozoa, each with a tadpole-like head and tail.
Researchers estimate this process takes around 74 days.
The sperm then travel through the epididymis, a tube behind the testes, before ending up at the vas deferens, another tube linked to the ejaculatory duct.
Lifestyle choices can affect sperm count
The number or concentration of sperm in an ejaculate sample commonly determines the sperm count. There is some evidence that lifestyle choices can affect this number.
For example, one large study found a link between smoking and a decreased sperm count. There is also evidence that dietary changes could play a role. For example, some research suggests that increased levels of vitamin D might promote sperm production.
Sperm count may vary with location and ethnicity
Scientists know sperm counts have been decreasing in many Western countries. According to one study, the average sperm count between 1973 and 2011 decreased by 59.3% in North America, Europe, New Zealand, and Australia.
Researchers do not yet understand what caused this drop, although it may be due to lifestyle changes.
There is also some evidence of a link between ethnicity and differences in sperm production. One study notes the following difference in the sperm counts of Latinx, white, and Chinese males:
- Chinese males produced 70–173 million sperm cells per day.
- Latinx males produced 231–398 million sperm cells per day.
- White males produced 193–318 million sperm cells per day.
The following are four sperm-related myths:
Briefs are bad for sperm count
Some people believe wearing tighter underwear can significantly lower a person’s sperm count. However, scientific evidence suggests this is an overstatement.
One recent study suggests that males who wear boxers have a 17% higher sperm count than those who wear briefs. However, the study authors acknowledge that these findings may not be reliable, as their research relies on participants’ self-reporting and recall, among other factors.
Pre-ejaculate cannot lead to pregnancy
Pre-ejaculation is when the penis releases a small amount of fluid before ejaculation. This fluid is known as pre-ejaculate.
Although pre-ejaculate does not function to deposit sperm into the vagina, it can pick up living sperm cells as it travels through the penis. For instance, one study found healthy sperm within 16.7% of pre-ejaculate samples.
For this reason, there is a small chance that exposure to pre-ejaculate could lead to pregnancy.
Sperm production doesn’t change with age
Many people believe that older males can produce sperm just as well as younger males. However, this is a myth. Although spermatogenesis continues throughout many males’ lives, sperm quality tends to decrease with age.
For example, research suggests that sperm from older males are more likely to cause genetic mutations in their offspring than sperm from younger males.
Sperm cells are great swimmers
A male body produces millions of sperm cells every day. In humans and other animals, sperm can move using a tail, or flagellum. This allows them to travel through the female reproductive organs, towards the egg.
This could give the impression that millions of sperm end up in a close race towards the egg, but this is not true. Many sperm cannot swim at all, or only very poorly. In fact, researchers know that many sperm cells move passively towards the egg.
If a person believes certain myths about sperm, it could lead to an unwanted pregnancy or other challenging issues. This is why people should know the difference between sperm facts and myths.