We all know when a man ejaculates during sex he releases millions and millions of sperm. Although these “sexy swimmers” come in high numbers, only a single sperm can successfully go upstream and fertilize an egg — and there is more to a man’s sperm than just fertilizing the egg to form a fetus.
Sperm live fast and die young. Men have a constant supply of sperm, producing at least 1,500 sperm cells per second. Since they live briefly, sperm supply must constantly be replaced, hence their astounding production rate. But just how valuable is good sperm health when it comes to creating a healthy fetus?
1. There’s a difference between 'sperm' and 'semen.'
Sperm and semen are mistakenly used interchangeably, but they are not the same substance. Sperm cells are actually a part of the semen, which is the whitish, viscous fluid released from the penis, according to MedlinePlus. Sperm leaves the body through the mix of bodily fluids that makeup semen. This fluid contains fructose and proteolytic enzymes that facilitate the mobility of sperm outside the male reproductive tract.
2. 90% of sperm ejaculated is deformed.
Not all sperm are created equal. Sperm can have a multitude of defects in the head, neck, or tail, such as two heads, two tails, and coiled tails — to name a few. These defects can potentially affect the ability of sperm to reach and fertilize an egg, but it does not mean men are infertile. Normal sperm, says the Mayo Clinic, have an oval head with a long tail.
3. Sperm is cold.
A man may get caught up in the heat of the moment, but his testicles stay cool. They are about 7 degrees Fahrenheit cooler than the rest of the body. This temperature is necessary to help healthy sperm stay chilled compared to the rest of the body. “Radiator-like” veins pull heat away while muscles in the scrotum raise and lower the testicles to bring them either closer to the body’s warmth or further away.
4. Sperm comes in both genders.
Not all sperm are chromosomally male. Several sperm do carry the X chromosome, while others carry the Y chromosome. However, female sperm is actually stronger than male sperm, according to Harvard Health Publications. This means the likelihood of getting pregnant by a female swimmer is higher than a male one. If a father provides an X chromosome, the baby will be female, whereas if he supplies a Y chromosome, the baby will be male.
5. It takes 2 months to make sperm.
It may take a second for a man to release 1,500 sperm cells, but it takes months to mature in the testes. This regeneration cycle takes about two-and-a-half to three months to fully mature. Healthy sperm will not be ready to fertilize an egg until a new set of sperm — developed in healthy conditions — matures.
6. One testicle can make enough sperm to form a fetus.
Men who have one testicle may be just as fertile as a man with two testicles. Typically, a man with two testicles will produce sperm and semen in both. However, if only one testicle is present, it will take over semen and sperm production. Although there may be reduced semen production, a man’s fertility is not affected in most cases.
7. Dead sperm can make healthy babies.
In vitro fertilization (IVF) makes it possible to use dead sperm to help form a healthy fetus. Typically, IVF technicians manually combine an egg and sperm in a laboratory dish and then transfer the embryo to the uterus, according to the American Pregnancy Association. Sometimes, a single sperm being inserted inside an egg may be “killed” after being beaten with a technologically advanced glass straw used for this process.
But as you can see, there's more to men's little swimmers than fertilization.