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All it takes is one healthy sperm to get pregnant.
But what it takes for that one sperm to get to the egg and fertilize is anything but simple. It takes a village.
A man releasing a single sperm – or a hundred sperm or even a million sperm – likely won’t get the job done. Men need to ejaculate at least 1.5 – 5 mL of semen to ensure one sperm results in a healthy pregnancy.
And we aren’t just talking about any sperm – we are talking about healthy sperm. At least 60% of sperm in a man’s ejaculated semen needs to be healthy to ensure a healthy pregnancy. Male infertility is responsible for 40-50% of all infertility cases.
It’s time to look at getting pregnant from the male fertility POV. A man’s sperm health, volume, count, and more play a big role in conceiving a healthy baby.
How much sperm do you actually need to get pregnant?
You need only one sperm to fertilize an egg. But you need a lot more sperm for that one little guy to make it to the finish line. Semen helps with that.
Sperm is the germ cell that carries the male’s DNA. And semen is the fluid in the testicles and prostate that keep the sperm safe. Semen is also responsible for nourishing and carrying sperm.
For pregnancy, a man’s ejaculation needs at least 15 million sperm per milliliter or more than 39 million total sperm.
Why?
Because the journey that the sperm needs to embark on to reach the egg is anything but smooth sailing. It is selective and grueling.
Even though you start with millions of sperm, only about 200 of them will reach the egg.
Wild, right?
Here’s a quick overview of the bumpy road the sperm takes.
Sperm → Ejaculation → Vagina → Cervix → Fallopian tube
So much happens in each of those steps that can cause the sperm to get lost or die. However, the entire process from ejaculation to the fallopian tube is fast. It takes only about 10-15 minutes.
For pregnancy to happen, you need to keep sperm inside of you. A study looked at laying still for 15 minutes to determine if that increases the chances of conception. The results? It only boosted pregnancy chances in assisted reproductive techniques (IUI).
If you’re trying to conceive naturally, you don’t need to lay down or put your legs up. Your body does the work for you regardless of the position.
Let’s look into each of these stages further. Note that it’s normal for the sperm numbers to reduce as you go through these phases. This does not mean that something is wrong and it is not linked to infertility.
Ejaculation
All of the sperm ejaculated during sexual intercourse does not stay in the vagina.
Pullout adds to the loss of sperm. While residual semen falls out of the vagina, there’s no need to worry. The sperm has already gone into the uterus by then.
Vagina
The pH of the vagina is hostile to sperm; it’s incredibly acidic. The vagina’s immune response is to kill the sperm because it’s foreign. This results in a substantial loss of sperm.
Cervix
Cervical mucus isn’t friendly to all sperm. Some of them get trapped in its stickiness, leaving only the most motile sperm to continue the journey.
Think of cervical mucus as your body’s natural process of weeding out the bad sperm. It allows only good sperm into the uterus.
Fallopian tube
The surviving sperm make their way to the uterus and enter the fallopian tubes. But only 50% of the sperm make it to the correct fallopian tube.
A maximum of 10,000 sperm cells (of the millions you started with) make it into the right fallopian tube.
And it doesn’t end there.
Once in the fallopian tube, the sperm has to pass 2 more tests to win the prize of fertilizing the egg:
- Capacitation. The changes that the sperm needs to undergo so it can successfully penetrate and fertilize the egg.
- Hyperactivation. This is the vigor with which the sperm swim. The more vigorously they swim and the more hyperactive they are, the better their chance of swimming up the uterine tube and penetrating the egg.
Out of the 10,000 sperm cells that made it to the right fallopian tube, only a few hundred make it to this next stage: reaching the egg. And it’s not the fastest sperm that meets the egg but the sperm that the egg chooses.
How exactly does the sperm get to the egg? By way of something called sperm chemotaxis. Progesterone secreted by the cells around the egg works as a chemoattractant for the sperm, guiding them to the jackpot.
But ultimately, only one sperm wins the grand prize of fertilizing the egg. Once it does, the egg forms a thick impermeable membrane a.k.a. “jelly coat” around it. This keeps additional sperm from getting in and fertilizing the egg, too.
So, the journey that started with millions of sperm ended up with a sperm count of about 200. And only one of those successfully completes the process.
It’s clear why sperm selection is considered one of “the most severe selection processes designed by evolution“.
So, yes – you technically only need one sperm to get pregnant. But it takes millions of sperm to get that one sperm to its final destination. Think of it like a team effort.
How can I increase the chances of sperm survival?
The more sex you have, the higher the chances the sperm will survive.
That’s because repeated sexual intercourse signals to the female body that the sperm is safe. It also shows the body it’s time to get pregnant.
Special sugar molecules on sperm cells (called sialic acid) tell the female’s uterine cells that they’re safe to enter. This allows healthy sperm to pass through the immune system while blocking the unhealthy ones.
Think of it like a secret handshake between the sperm and the female immune system.
The woman’s immune response against the sperm declines which increases the chances of sperm survival.
How much sperm is needed to get pregnant with artificial insemination?
The journey for artificially inseminated sperm is a unique one. The sperm get a shortcut and are directly inserted into the female reproductive tract.
This means fewer sperm are needed for artificial insemination (a.k.a. intrauterine insemination (IUI)) than with natural ejaculation.
One study found that for the best success with IUI, you need a sperm count of at least 6.7 million healthy sperm to get pregnant.
How do you know if you’re producing enough sperm to get pregnant?
Since you can’t exactly see individual sperm to count them, how do you know if your sperm count is enough or whether you’re dealing with a low sperm count?
You can do a semen analysis either at a lab or at home. A semen sample is used in either method to measure the sperm count. At home, you’d use a testing kit to guide you.
Here are the numbers to remember:
- Sperm count > 39 million per ejaculation
- Sperm concentration > 15 million per mL
Keep the numbers above that, and you should be in business.
What are the other sperm factors that help you get pregnant?
While sperm count and volume are important, sperm quality is too. Men need to produce healthy sperm to get their partner pregnant.
Motility
Sperm are natural-born swimmers. But just like humans, some sperm swim better than others.
Sperm motility is the ability to swim, which is key to the sperm making it to the egg.
As we talked about earlier, these sperm need to be super motile so they can make it through all the different hurdles on their journey.
You want sperm with progressive motility. This means they swim in straight lines or large circles. They’ll need those skills to navigate the female reproductive tract.
Sperm that have non-progressive motility move in less efficient ways.
At least 32% of your sperm need to be progressively motile for the best chances of pregnancy.
Morphology
In this case, size does matter.
The size and shape of your sperm are referred to as morphology.
Normal sperm look like the image you probably have in your head: an oval head with a long tail. This is important for the sperm’s ability to swim and penetrate the egg.
The good news is that you don’t need all your sperm to be normal. But you do want at least 4% of them to have normal morphology.
DNA fragmentation
The DNA of the sperm is directly correlated with the quality of the sperm.
While not all of the sperm need to have healthy DNA, at least 70% must. The lower the percentage of fragmented DNA, the lower the risk of fertility issues.
If you’re looking at more than 30% of fragmented DNA in the sperm, it’s cause for concern.
A semen analysis with a fertility specialist will help give you a picture of your sperm health.
Learn more: Semen Health: How To Produce More Sperm?
Does increasing sperm volume increase the chances of conception?
It’s fair to think that more is better when it comes to sperm volume.
But the truth is, it’s not.
The most important things when it comes to semen for a successful pregnancy are:
- Sperm count
- Sperm quality
Studies support this and show that – beyond the minimum required count – there isn’t a big difference in conception rates with an increase in sperm count.
In review
- How much sperm does it take to get pregnant? It only takes one sperm to fertilize an egg.
- But you need millions of sperm to boost your chances of success.
- A good sperm count is greater than 15 million/mL or at least 39 million sperm per one ejaculation.
- Millions of sperm die in the journey through the female reproductive system.
- The sperm get ejaculated into the vagina, then the cervix, the uterus, and finally into the fallopian tube.
- Only about 200 sperm actually make it to the egg.
- That’s because sperm has to make it through the acidic vagina, sticky cervical mucus, and into the right fallopian tube.
- A semen analysis uses a semen sample to determine the quantity and quality of sperm.
- Sperm motility is the sperm’s ability to move in a straight line and large circles. 32% of the total sperm need to have progressive motility.
- Morphology refers to the sperm’s shape and size. Normal sperm has a large oval head and a long tail. At least 4% of sperm should have normal morphology.
- At least 70% of sperm should have normal DNA.
FAQs
Only one sperm is needed to get pregnant. But you need a sperm count greater than 15 million sperm/mL of semen or 39 million per ejaculation to ensure that fertilization can occur.
The sperm needs to be inside the vagina in order for it to possibly get a woman pregnant.
Once semen is discharged, the sperm takes about 15-45 minutes to reach the egg. However, if you haven’t ovulated yet, it could take longer. Sperm can wait inside the reproductive tract for an egg for up to 5 days.
It takes at least 1.5mL of semen to get pregnant.
It’s possible, yes. All it takes is one sperm to get pregnant. But many sperm get lost or die along the journey to the egg.
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- Trends of male factor infertility, an important cause of infertility: A review of literature | NIH
- Fertilization | NIH
- Immobilisation versus immediate mobilisation after intrauterine insemination: randomised controlled trial | theBMJ
- Optimizing natural fertility: a committee opinion | Fertility and Sterility
- Why so many sperm cells? | NIH
- Sperm may offer the uterus a ‘secret handshake’ | ScienceDaily
- Sperm selection in natural conception: what can we learn from Mother Nature to improve assisted reproduction outcomes? | NIH
- Sperm Transport | ScienceDirect
- Molecular Mechanism for Human Sperm Chemotaxis Mediated by Progesterone | NIH
- How Much Sperm Does it Take to Get Pregnant? | NIH
- Minimum number of sperm needed to obtain an intrauterine insemination pregnancy | Fertility and Sterility
- When to Have Sex When You Are Trying to Get Pregnant? | Inito
- Current Insights and Latest Updates in Sperm Motility and Associated Applications in Assisted Reproduction | NIH
- Semen Health: How To Produce More Sperm? | Inito
- Tips for Getting Pregnant with Low Sperm Count | Inito
- Sperm Transport From The External Cervical OS to the Fallopian Tubes in Women | Fertility and Sterility
