Help settle a debate: which ejaculation/sperm fertilised the egg?

[Poppins2016]

Nope, it's not what you think, I didn't have an affair 🤣

DH and I are having a debate. I can't easily find any information online to back up my argument so I'm turning to MN!

DH thinks that the most recent ejaculation is always the one that will fertilise an egg.

I think that any ejaculation/sperm is (potentially) viable to fertilise an egg from about 5 days prior to ovulation/conception. Most sources state that sperm can live up to 5 days 'in waiting' for the egg as long as fertile cervical mucus is present.

Presumably a new ejaculation doesn't 'wash away' the previous...?!

Bump 🙂

I agree with you. It’s not always the most recent. It’s whoever gets to the egg first, surely? And sperm live for ages.

If anything, the longest-standing ejaculate should get there first as they have a head start? 😂

I watched a really interesting YouTube video about this! 😄 As soon as a sperm reaches the egg and burrows in successfully, the egg basically closes for business and the rest of the sperm have nae chance.

So I guess ones that are already on their way/nearly there when the egg gets to the fallopian tube have the best chance.

No you're correct, it's the best swimmer lol so you could have sex on the Tuesday and Wednesday, ovulate on the Thursday and then have sex again only for a sperm from Tuesday to fertilise the egg! And yes it does close for business once a sperm has got in lol

Also, did you know that it's like a massive assault course for the sperm once they've been ejaculated, the woman's body tries to kill them off at several different points 😆 I watched it on YouTube it was crazy

Can someone please share the YouTube video!

Agree, it's not just the one that reaches the egg first though - I'm sure I learned that some sperm will arrive as a faster sperm is getting tired of trying to break in. The first sperm having done the hard work, the arriving sperm swoops in to fertilise.

Also Y sorry swim faster than X sperm , so depending on when the egg was released will mean which sperm is more likely to reach it.

e.g. Sex before ovulation, Y sperm swim fast but there’s no egg when they get there, the slower X sperm gets there just as egg is released.

Sex after ovulation, Y sperm get to egg first.

Sorry = sperm. Fabulous autocorrect

The fastest so could be newer. Sperms die so they might not make it
So 2 sperms never? Twins is always
Identical 1 sperm 1 egg splits as an error
Fraternal 2 eggs 2 sperms just happened to get pregnant at the same time. So maybe 2 eggs from 1 tube or 1 from each and its coincidence

Biology is mad!

I think this was the one I watched

Sperm work in teams to digest through the jelly layers of the egg as each sperm doesn't have enough enzyme in its head to do the job alone. Then the egg layers separate on a process called the acrosome reaction.

They work in teams ? Madness !! Are they like teams from the same batch against another batch 😂

So every one of us is the product of a gang bang? Wild.

This is fascinating, I didn't expect this much (additional) information! 😁

But essentially (and importantly 🤣) it looks as though I'm right?!

I can't remember where I read it. But I'm pretty sure I read a study to the effect that you're more likely to conceive if you have sex 1 or 2 days before ovulation. In which case you imagine the earlier sperm may have an advantage.

This isn't the one I was thinking of. But it shows that your chances of conceiving in the two days before ovulation are pretty much the same of conceiving on the day of ovulation. So I'd say that earlier sperm may be just as likely to fertilise the egg.

Biology is mad!

... and fascinating!

Thanks for all the input and links to YouTube/studies.

🙂

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1440662/

Thanks for that @ShowOfHands . I stand corrected.
I did google before I posted, so it seems there is a lot of that misinformation out there.

Thanks for posting this. I was aware of the shettles theory having been debunked, but it still seems to be referred to surprisingly often (in articles, on MN... lots of people claim the method was successful, but I suppose it's confirmation bias)!

That's really interesting!