Sperm are some of the tiniest cells in a man’s body. They’re responsible for delivering genetic information to the egg, so it has enough information to become a baby. Sperm travel from the “sperm factory” in a man’s testicles to his sperm duct and into your vagina. Then they swim through your cervix and uterus, and eventually reach the end of your fallopian tubes. Here, the sperm will fertilize your egg (if an egg is ready and waiting). Sperm are released by the hundred million, so their odds are good!

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The science of sperm

Unlike women, who are born with all the eggs they’ll ever have, men don’t even begin to produce sperm until they reach puberty. A man’s testes are where sperm cells are created. These young sperm cells then travel into an area of tightly coiled tubes just above the testes, called the “epididymis”. They stay here until they’ve matured.

This whole process takes about 70 days to complete, and happens continuously throughout a man fertile life.

When the sperm cells are mature, some of them mix with seminal fluid (produced by a man’s prostate) to create semen. Semen can then be released from the man’s penis into your vagina.

Once sperm are in your vagina, they’ll swim up through your cervix and uterus. Neat fact: if there’s an egg present, they’ll pick up the egg’s chemical scent to figure out with of the two fallopian tubes the egg is in!

If there’s no egg, the sperm can live in the woman’s body for up to five days, waiting for an egg.

When the sperm and egg finally meet, the sperm will compete to be first to penetrate the egg’s outer layer. Once inside, the egg will unravel the winning sperm’s densely packed DNA and begin to fuse the genetic material with its own.

Mission completed, the fertilized egg then travels into the uterus to implant!

The most successful sperm have two qualities: they’re great swimmers, and there’s a whole lot of them!

But don’t worry: sperm that only have one of those qualities can still fertilize an egg. (For example, if there’s a huge amount of not-so-great swimmers, or a small amount of terrific swimmers).

10 easy ways to help your sperm

  1. Avoid excessive heat, like hot tubs or saunas.
  2. Limit coffee to one or two cups per day.
  3. Don’t smoke or do drugs, even marijuana. Marijuana can affect your sperm for over two weeks!
  4. Don’t drink more than two ounces of alcohol twice per week. Alcohol is a male reproductive tract toxin, and it’s associated with a decrease in the percentage of normal sperm.
  5. Maintain good eating habits. Fresh fruits, leafy vegetables, and red meat (if possible) can help.
  6. Exercise regularly and moderately (don’t go on any crazy diets).
  7. Antidepressants may decrease sperm counts, so if you’re taking them, don’t worry if it takes a little longer to get pregnant. Be patient.
  8. Be aware of sexual problems and don’t be afraid to ask for medical help. It’s nothing your doctor hasn’t seen before.
  9. Be in good emotional shape. If you’re struggling with feelings of stress, insecurity, or other problems, don’t wait to ask for help! Talk to someone who supports you, or find a therapist you like.
  10. Educate yourself about health and reproduction.

Fertility challenges

Remember that the most successful sperm have two qualities: they’re great swimmers, and there’s a whole lot of them! But if you have a small number of great swimmers – or a large number of weak swimmers – it’s still very possible to get pregnant.

Low sperm count

A low sperm count is a common problem, and it isn’t necessarily serious. The prognosis is generally pretty good, and natural pregnancy is quite often possible.

Why? Because a low sperm count means, of course, that there are still sperm present. Sperm are generally present in the millions, or at least the thousands. And it only takes one to get pregnant.

So it’s reasonable to remain hopeful that sperm will ultimately enter the egg. Just, perhaps, not the first egg. Or the second. If it’s been six to twelve eggs (6-12 months of trying) with no other causes for subfertility, then it’s safe to conclude the low sperm count is playing a role.

Why might this be happening? Common causes of low sperm count are hormonal issues, autoimmune issues, lifestyle choices like marijuana or smoking, varicoceles (dilated veins that heat up the stem cells in the testes), or injury.

Sometimes we can reverse low sperm counts. But sometimes we can’t, and counts remain low. You could try inseminations of sperm (also known as a “sperm wash”), but the success rates are often limited. The best success rates come from IVF with ICSI, when sperm are placed within the eggs.

Nobody wants to leap into IVF/ICSI. However, there’s good news: if the eggs are good, if your partner is healthy and her uterine structure is normal, and if the DNA inside your sperm are consistent with a healthy pregnancy, then you’ll have an excellent chance at pregnancy with IVF/ISCI. Low sperm counts are a frustration, yes—but they aren’t a hopeless fertility problem by themselves.

No sperm at all

A more serious problem is when there’s no sperm in the man’s semen at all. That’s a condition called “azoospermia”. This can be caused by a tube being blocked, or problems with the production of the sperm itself.

If it’s a blocked tube, it’s usually on purpose (when a man has a vasectomy procedure). However, it can be caused unknowingly by other surgeries or infections, and is associated with carriers of cystic fibrosis.

The good news is that tubal obstruction is often repairable through surgery, and the prognosis is typically good!

If it’s a sperm production problem, it’s more complicated and the prognosis is usually less promising.


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