| HealthLine – Sperm exit the penis, enter the vagina, and swim north until the lucky one reaches the egg to fertilize it – right?
Actually, it isn’t quite that simple.
Many of us believe some long-standing sperm myths. Here are some common ones.
1. Sperm swim like Olympic athletes
The common tale is that millions of heroic sperm swim in competition with each other to be the lucky little swimmer that penetrates the egg.
First, sperm don’t necessarily swim straight. Sperm motility is classified into one of three groups:
- progressive: actively moving forward
- non-progressive: any other pattern except forward
- immotile: not moving
Sperm require more than a little boost from the female to get to the finish line.
In fact, most of the motility work is done by the uterus muscles. It coaxes the sperm along to the fallopian tubes, towards the egg.
2. Thicker sperm is more fertile sperm
Thicker semen doesn’t necessarily mean thicker sperm.
It could means there’s a high concentration of sperm, or just a high number of irregularly shaped sperm.
They still need help from the woman.
In the vagina, sperm come into contact with cervical mucus, which does two things: protects and rejects.
It protects sperm from the vagina’s acidity as well as rejects sperm whose shape and motility would otherwise keep them from reaching the egg.
3. Sperm only live for a short time after release
Not always! Lifespan depends on where sperm land after ejaculation.
Sperm that make it into the vagina can live up to five days. This is due to the protective effects of cervical mucus and cervical crypts.