Life Science

Why are over 250 million sperm cells released from the penis during sex?

Asks Nessa from London

June 2, 2008
Credit: Molly Ashford
Credit: Molly Ashford

“Every sperm is sacred. Every sperm is great. If a sperm is wasted, God gets quite irate,” goes the song from Monty Python’s movie The Meaning of Life. If the lyrics strike you as funny, it’s most likely because calling a sperm cell “sacred” sounds ridiculous when men can produce so many of them.

In fact, the average male will produce roughly 525 billion sperm cells over a lifetime and shed at least one billion of them per month. A healthy adult male can release between 40 million and 1.2 billion sperm cells in a single ejaculation.

In contrast, women are born with an average two million egg follicles, the reproductive structures that give rise to eggs. By puberty, a majority of those follicles close up and only about 450 will ever release mature eggs for fertilization.

But if it only takes one sperm and one egg to meet and create a baby, then why do men produce such a whopping number of sperm? Wouldn’t it be less wasteful for a man to release a single sperm, or at least fewer, to meet one egg?

The reason for this predicament boils down to two words: sperm competition. Since the dawn of the sexes, males have vied with each other to get as many of their own sperm near a fertile egg as possible. Getting more of your sperm closer to an egg means there is a greater probability that it will be you and not your neighbor fertilizing it.

This kind of competition is an evolutionary imperative for males of any species. If a rival’s sperm fertilizes an egg, then an opportunity to pass on your genes is lost. Through many generations, as the reproductive spoils continually go to the highest sperm producers, their genes are passed on. The genes of the smaller sperm producers are eventually weeded out of the population and become a footnote to evolutionary history.

But if it was just a matter of ‘more is better,’ then animals of all species would have evolved ridiculously large testicles in a bid to overwhelm the competition. But it’s not quite that simple—numbers are important, but so is proximity. Fertilizing an egg is not just about how much sperm you can produce. It is also about how close you get your sperm to it.

In the early 1980s, researchers in the United Kingdom and the United States realized that both proximity and number were important factors in the physiology of primates, including humans. In primate societies with rigid social structures and one dominant male who mates with all the females, testes trend towards the small. In gorillas, for example, they are very small relative to body weight. (Don’t tell them that.) In gorilla society, one male defends a harem of females to ensure only his sperm gets anywhere near their eggs. In this case, making a lot of sperm doesn’t really help the male gorilla get the job done.

For chimpanzees, on the other hand, sperm competition is a serious issue. In chimpanzee society, many males and females live together in large troops, and females have sex with many males in a short span of time. This is why male chimpanzees possess the largest testes of all the great apes, weighing in roughly 15 times larger than gorillas, relative to their body weight. This gives them a better shot at swamping out the competition.

Human males fall somewhere in between gorillas and chimps. The average man’s testes are roughly two and a half times as big as a gorilla’s but six times smaller than a chimp’s, relative to body weight. This has led some researchers to question whether sperm competition was ever at work in human societies, or whether our relatively large testes are just a hold over from an earlier period in our evolutionary history.

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bob says:

this is sexual and i love it soooo much

Sandrey says:


Creation by God says:

Evilution, a theory and a religion. Yawnnnn

Jorge says:

If the ratio of sperms and eggs are right (and I have no reason not to believe the content of the material herewith), then that makes you in 1 in a billion!! And yet your finger prints are unique. There’s no other you. Now that’s sacred! That’s awesome! How great is God! How creative is He! Read Romans 8:29-31 for more information.

Dr. Steven Lafer says:

I prefer to trust in God because man and and other creatures evolved because God wanted it that way!

Shefcan says:

I just ejaculated 100 million sperms to my Molly… :D:D:D:D:DD:D

HAHA, she really loved it!
She wants it again!

Their all in her stomach….

But she says that they all gonna die.

I don’t want them to die, please…

C’mon let me give you again,

This time I’ll give 200 million.


Are you kidding? says:

God wanted it this way? You’ve got to be kidding… God must have wanted the holocaust to right? Good thinking Jew killers…

Kathy Snyder says:

I think the bigger picture is to teach preteen males about their role as sperm protectors. The relationship between male and sperm should precedes all other relationships as a guide for the treatment of all other living beings. Males as nurturing and protective – I’d enjoy a world full of these males!

hayley says:

eww this is the most wrong thing ever eww

Juwohn Emmi says:

This is pretty interesting nd cool…………God is great

curiouspirit says:

LMFAO at the first few lines….

smarterthanyou says:

God does not exist. but this is incredible :)
Science.. not religion.

Tech not Bible says:

Ummm, wow to #8 comment(never going to happen)…. and I personally agree with #12
Science——-Not religion.

kvn says:

very informative lol

Simon says:

That is a lot of sperm.

Donatus says:

it’s not a mistake for God to have made the human race to be so.

ech says:

Why did God make the journey of the millions of sperm to the egg so similar to the annual journey of the salmon from the ocean to the freshwater spawning grounds? Sperm face the same obstacles along the way as salmon: fighting currents, bacteria, rocks, hungry bears, acid, tight passages (fallopian tubes), etc. most dieing along the way and only a few ever reaching the final destination. Sperm even swim like a fish.

Steven says:

I was gonna site this site for a lab report, but then I read all the comments about God. I better not site something like this in a scientific report. Any bright person who thinks rationally will eventually come to the conclusion that God either doesn’t exist, or that he just DOESN’T GIVE A DAMN about his creation. Or maybe he thought it would be fun to create someone like me and then send me to hell because I thought too rationally about him…Why did God equip us with rational power and then hope for us not to use it and use faith instead?

luis says:

i think i know y god gets mad because we wasting our children and some other people who want to get kids they cant. thats why important ton not wasted

miguel says:

ALL of us, each human Being in this planet, are fertalized sperms chosen from among many other sperm cells as you can see. Perhaps that’s what Jesus meant when he said: “No one can come to me unless the Father who sent me DRAW him,…” Jh 6:44 We were drawn from about hundreds of millions! That’s HUGE! Now you see why God sees us as something special.

I too get angry at God because I don’t see the big picture and can not appreciate how it is to his/her greater glory for the world to be as it is. I have tried to be cold and say that there was no creator but somewhere deep within myself I just feel that there is something out there greater than myself. I choose to call that something God. Bottom line; whether you believe in heaven or hell is of no relevance to me. What I do believe is that if this is our only chance to live and to be aware of our existence, then how do I want to live my life? Do I constantly want to be full of hate and bitterness; pointing my finger at that church or at that non-believer? or do I want to live a life full of grace and peace; trying to make our short time here a joy rather than a burden? I can’t sell you God but I can share with you what the Spirit has done for me in my life. Beyond that you must search your own hearts and decide how you want to live your lives. I consider you to be a calculated miracle; not a chance fertilization – and that makes you pretty special in my book. So, if no one has ever told you before then hear it now; you are unique and there is something within you that only you have been chosen to do. Open your hearts and place your intellect on hold. The Spirit of God lives within each and every one of you. Thank You for at least listening.

Blozcot says:

Why do so many people insist on choosing between God and science? It can be both. Maybe all of our scientific observations are completely true, and God made them that way. Maybe every single atheistic argument is valid, but God created the universe so intricately that it looks like it all evolved by chance.

He may have even done this on purpose. God’s wants us to have faith in Him, and you cannot measure faith without the existence of doubt.

A muslim says:

Before anyone judges a muslim on the basis of the incident of 9/11 and the “19” that were involved and used that as a reason for ridicule and prejudice… Id like to throw a rational stance to the science and religion argument. I invite everyone to take a look into the Quran. It is taken by muslims to be the direct words of God. Now dont be bias… Theirs a few things you can take and look for urself. A challenge produced by it is “if this book had been from anyone other than God you would have found many errors/contradictions”. Now the book is abt 1500 yrs old and described vividly the stages of embryology… 1500 yrs ago… Which science agrees to. The sperm being placed within a threefold darkness as mention in embryology textbooks. Mentions the moon having reflected light from the sun proven in astrology. The orbit of the moon describes as an over and under pattern between the earth and the sun and being twisted like a date palm branch when it withers also proven in astrology. Sirius being two stars instead of one. The mountain being as pegs into the earth as seen in study of tectonics. Everything having a pair. Particles existing smaller than atoms. Iron being a product of asteroids and meteorites and not being a product of the earth. The water cycle. The roundness of the earth compared the the geospherical shape of an ostrich egg whch also science proves. And aside from scientifical miracles you have spiritual miracles like the body of pharoah found by a world renowned surgeon by the name of maurice bucaille tested the body and deduced its the body of pharoah still intact organs and all. Which later he found out that God says to Pharoah(of moses time) that he will preserve his body as a sign for mankind. Which lays in the museum of ancient egypt with the verse beneath the case. Anyone can read it for theirselves and i hope you can put bias aside and have a read. I can go on longer about the scientific aspects of the Quran for days as i have done much study in both the Quran and in science but im cutting short for the sake of reducing my post. I recommend a yusuf ali translation if anyone decides to look into it. It says that its a confirmation of older scriptures too so christians and jews alike will find much familiarity. And one difference that God is above being a man, and that hes greater than anything being associated with him in his Godship. Salaam(peace)

Al Ragan says:

Consider this: Modern humans date back 60,000 years or so but if you go back to “Lucy”, one of the very earliest ancestors, your “Family Tree” may contain over 200,000 pairs of specific people who ultimately produced YOU. That’s nearly 1/2 million specific persons, each contributing half a strand of 23 chromosomes, each being strong enough to live long enough bear offspring, with each female producing up to 450 eggs and with each male delivering 40 million to 1.2 billion sperm in each ejaculation (with the likelihood that none of the sperm may be exactly the same). If you are reading this, then there is a 100% chance that you made it! Congratulations…I’ll leave what the exact odds of you being here to a statistition (and hope one will figure it out and report on this site). But, generally – to me – it seems like the “odds” that YOU are here are indistinguishable from the ODDS THAT YOU WERE NEVER BORN!
Consider that! We should consider that daily. We should understand that if nothing else, that makes US wonderfully, awesomely special (and different). When I was a teenager, I worked hard to be “different” – to be my “own person” – to be an “individual”. In reality, I already was those things and now I realize that I was different the whole time! As the song states: “I am the one and only me”…and… “you are the one and only you!”
Consider that? We ought to but we don’t! To me this is one of the few places where spheres overlap; where the really big things become indistinguishable from the really small.
Now imagine this: “He called you by name before He set the foundation of the Earth” – before He separated the dry land from the sea!
Ain’t that cool?

Mickel inyang says:

God create a particular thing for a pupose so sex was not for unmarried damsels and guy so pls stop

uhhh what? says:

Okay.. number 25… you do realize sex WAS made for unmarried people? It’s called mating. You don’t see apes getting married, you don’t see dogs proposing before hopping on the back of a bitch in heat. That’s what sex is about: continuing you’re line of genes and growing the population. At some point something happened and we became rational creatures who fell in love. I believe this is known as evolution. So, yeah… You’re statement is completely untrue… Also tell that to the pedophilic priests raping small children.

simon says:

if a man produces all those spearms in a life time is there a chance of being impotent if he is musterbating fr over five years continusly

tankdude says:

It is a sin to have sex when u r not married.

A Doss says:

Hi everyone, who said faith is not rational ?!!

gbcnes says:

I believe in God it is great. without God you can be in theis word

Nice answer back in return of this query with firm arguments and explaining everything regarding that.

james says:

The very high ratio of sperms to single egg in each human copulation is that the healthiest, strongest will win the battle of fertilization. ^_^

bob says:

lol this is funny

LEE says:


LEE says:

What this is funnyyy!!!!

ioyhh says:


Priyo says:

Can I increase my sperm???

Kayfabe says:

This is stupid! So if aguy has sex with a woman what exactly are all these sperm competing against? Every one in there will be from that same guy, there is no other sperm in there to fight with over fertilization in the first place! Because either the woman had sex before with different guys, but not within the last five minutes! All the other sperm that was ever maybe inside her body has long since gone, washed away, died Etc. There is nothing to compete FOR! Humans bormally just have sex with one person at once. Even those small percentage who have it with several people, only one can enter the vaginal area at once. There are zero situations where one woman is being filled with sperm from hundreds of men within an hour or whatever, for the reason of making a child! Does not happen there is no sperm competition unless your own sperm are trying to beat out others of your own same persons sperm! And no woman who allows many guys to one after another have sex with her, is EVER doing so to find the strongest sperm to give birth! That is just annorgy or purely sexual, not for a child. And anynother situation where a woman is being entered by tons of different guys within minutes, will be called a gang rape- also not with any intent on producing a child! There IS no ” sperm compeition” lin humans and I doubt there ever was even in cave days, most likely a woman had sex with the man she did it with and only they had a child. This is stupid to even think pertains to hans. This is strictly for non human, animals who have no sense of a two person couple.

Kayfabe says:

Oh another thing humans need to STOP having children altogether, and then eventually limit to one child only per couple or person. Overpopulation is totally unecessary and stupid. There are zero reasons for majority of us to ever have even one child and these days who the heck CARES if their genes live on? No one. Maybe stupid royality thats it, but no one should thats dumb. Stop breeding! Learn that life is perfect childless you can be and have anything you want go where you like, have all your income for yourself! No stupid children to demand things or have needs. You are free and happy! Not having a child in life you are only missing out on BAD stuff, your missing zero good things and adding so much good stuff in life by not being shackled down by a selfish needy stupid kid. I chose to have no children. Best choice I ever made and everyone else should try it too! Theres too many humans and over half do not even have purpose or deserve to live, wastes of space. Let the human race die off for awhile, I say about 25 years no breeding allowed. Then you can begin only having ONE each. Punish those who have more, reward childless couples, and population problem GONE. More resources for the rest of us who actually deserve them for not adding to the problem!

zach says:

so if this article is right than any boy can only jack off under 525 times, i think that is wrong, i dont know a ton about this but that number just seems really low and off

Fabian says:

We are God, we’re science nature, stardust and everything else.

Citations citations citations says:

What are your sources? Thank you.

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