They don't call life a miracle for no reason, and when you look into exactly how we end up being pulled out crying into the world, it's amazing any of us are here at all.
Anywhere between 40 and 250 million sperm are released in the average ejaculation, while as few as 20 end up reaching the fallopian tubes in hopes of encountering an egg.
Even though all it takes is one sperm to make it to trigger fertilization, the odds aren't exactly in our favor.
The fastest a sperm can reach an egg is 30 minutes, although some can take up to 12 hours. During that time, these poor little swimmers are running a veritable gauntlet of obstacles, with the human body designed to attack sperm.
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It's been a pretty vagina-heavy week at UNILADTech, with the latest vaginal video coming shortly after biohacker Bryan Johnson boasted about the health of his girlfriend's vagina. We already know what happens to sperm that isn't ejaculated from the male body, but what about those tadpoles that go on their intended mission to try and further the human race?
In a shocking science video from the BBC, we learn how a woman's immune system will actively attack sperm with the intention of protecting her precious eggs. As sperm are considered 'foreign' to a woman's body, it makes sense that defenses are up and it tries to prevent these 'unwanted invaders' from getting too far.
The simulation shows how sperm entering the cervix are in a labyrinth of dead ends that are perfect for an ambush.
A woman's reproductive tract initiates a controlled inflammatory response, with leukocytes (white blood cells) phagocytosing faulty sperm, ones that appear abnormal, or any that have lost their ability to fertilize. While this is natural selection at its finest, it's staggering to think how many sperm perish on their way to the egg.
Due to sperm containing foreign proteins that aren't found in the female body, the leukocytes are poised to attack. If that wasn't bad enough, the fact that the acidic PH of the vagina serves as a primary protection against bacteria also means many sperm are caught in the crossfire.
In graphic detail, the simulation shows white blood cells attacking those intrepid sperm from all directions.
By the time survivors reach the safety of the fallopian tube, their ranks have dwindled, and only a handful of survivors remain.
Thankfully for sperm, they contain molecules that help protect them from the immune response, ensuring that the ones who make it this far are the most motile and fit.
In some extreme cases, a woman might develop an allergy or a stronger immune reaction to semen, which can result in burning, itching, or swelling in the vaginal area, as well as pain during intercourse and redness after sex.
Either way, it's truly fascinating to realize how hard it is for that one sperm to fertilize an egg.
Responding to the video, one person said: "When your mom says you haven't achieved anything yet.....Show her this."
Another added: "I just want to thank the 149,999,999 lost brothers and sisters who died for my cause."
A third concluded: "When you realize we survived a massacre at a microscopic level."
The worst bit is that a woman's egg is also selective, so swimming up to the front door is actually just half of the battle.