> Another common and ridiculous meme is the "pregnancy after having sex once" idea.

Are you suggesting the odds of that are so low that they’re laughable? Because they’re not..

There's only (approximately) two days a month when a human female can get pregnant. It's not about frequency or intensity, rather it's mostly timing. (And sperm quality, but that's another thing people have no clue about.)

Sperm can hang around in the fallopian tube for almost a week. It's also possible to ovulate without a visible period, and it's possible to ovulate in-between "normal" periods.

Don't assume any hard-and-fast rules when it comes to fertility, and definitely don't assume that somebody can only get pregnant two days out of the month. Our species would never have survived if that was really true.

Biology is messy, imprecise, and very subject to external effects.

I was going to say three days, but it doesn’t matter. That’s 7% then turn it into a birthday problem (the world’s full of people having unprotected sex for the first time with someone at any given time) and there you go. Deduct points for bad form or bad sperm and it’s still a crazy number. It’s only a talking point when it’s the case, so it’s bound to sound like it’s happening to everyone.

> Obviously these people never experienced pregnancy.

It's the high end, so that's the threshold if you're using a particularly picky definition of 'sentience'. It seems like a defensible position to me, that if you stopped brain development around 30 weeks you wouldn't see much self-awareness.

Another common and ridiculous meme is the "pregnancy after having sex once"

I don't understand what your point with this.

Women's libido is heightened around ovulation (and men react to that), the menstrual cycle can be irregular (specially before the first pregnancy).