Are men born with sperm?

Dear Don't Know!,

Yes, men are born with sperm. But technically, they're not sperm... yet. In the same way that women have a specific quantity of immature eggs at birth, baby boys are born with what appears to be a set number of undeveloped sperm cells. These precursors eventually become mature sperm after they reach puberty, which is similar to women producing mature eggs after they start menstruating.

For women, eggs that are prepped for ovulation are not replaced. A woman's eggs typically stop maturing with the onset of menopause. In contrast, a man's supply of sperm is continually replenished. This process, known as spermatogenesis, continues throughout a man's adulthood. But let's go back to the beginning...

Basically, the entirety of a man's sperm production stems from the original, undeveloped sperm. That is, these immature sperm cells make exact copies of themselves. These originals are then saved for future use, while the duplicates transform themselves into four mature sperm each. However, if all of a man's original, undeveloped sperm cells were damaged or killed, he would be sterile because his body no longer has the resources necessary to produce more sperm.

Hope this information floats your boat!