Sex education in the United States is just about the best it’s ever been… and that’s not saying much.
As of 2025, 29 states and the District of Columbia mandate sex ed. Of those, only 13 require that students receive medically accurate information.
Most American adults are sexually active, yet many of us are ill-informed or misinformed about what that entails. It’s up to us to learn what we were never taught in school. So here are seven relevant sex facts that aren’t covered in the average classroom:
1. Vaginal canals vary in length, similar to penises.
You’re much more likely to hear a group of men competing over who has the largest penis than to hear women discussing the depths of their vaginas — but there’s variation in both reproductive organs!
The average flaccid penis is about 3.6 inches. Most unaroused vaginas are 2 to 4 inches deep. Once the blood starts flowing, the average erect penis reaches around 5.1 inches, and the vaginal canal expands to 4 to 8 inches deep.
2. Frequent ejaculation seems to decrease the risk of prostate cancer.
Although scientists can’t pinpoint why, multiple studies have found that the more often someone with a penis ejaculates, the lower their risk of prostate cancer. One Harvard study found that ejaculating 21 or more times a month decreases the risk by 31%!
Perhaps it’s best not to participate in No Nut November…
3. Intersex traits are about as common as having red hair.
This fact depends on how you define intersex. When only considering babies born with genital differences, the statistic drops to about 0.05% of people.
However, when the definition is expanded to include those with subtler forms of sex anatomy variation — internal or hormonal traits — the intersex birthrate reaches 1.7%.
4. Most of the clitoris is an internal organ.
What most people think of as the clitoris — the nub at the top of the vulva — is actually just the glans, or head, of a larger organ. The entire clitoris is predominantly internal and several inches long. It’s shaped like a wishbone, with legs and bulbs that extend from the glans to around the vaginal canal.
The mythical “G-spot” is now thought to be a sensitive area that stimulates the internal clitoris, urethra, and anterior vaginal wall.
5. Different lubes should be used at different times.
There are three types of lubes: water-based, silicone-based, and oil-based. Each type has its own benefits and drawbacks.
- Water-based lube is easy to clean up, works well on sensitive skin, and is compatible with condoms and toys. However, it dries out quickly, so reapplication is often necessary.
- Silicone-based lube is long-lasting and very slippery, making it a popular choice for anal sex (the anus provides no natural lubrication). It can be tough to clean up because it’s not water-soluble, but that also makes it a good choice for shower sex! Just make sure not to use it with silicone sex toys, as it can degrade the material.
- Oil-based lube lasts longer than water-based lube and can feel very smooth, but it cannot be used with most condoms. The oil breaks down latex, increasing the risk of condom tears.
One last note on lubes: the vaginal pH range is 3.8 to 4.5, and the rectal pH range is 7 to 8. It’s best to choose lubricants that don’t disrupt the natural pH of these organs. Vaginal lube should have a pH of around 4, and anal lube should fall between 5.5 and 7.
6. Most STIs are asymptomatic.
A vast majority of people with STIs, such as chlamydia, gonorrhea, herpes, and HPV, show no outward signs of infection. But just because it isn’t symptomatic doesn’t mean it isn’t transmissible.
Most cases won’t look like the fear-mongering photos in a health class — in fact, they won’t look or feel like anything at all — so make sure to get tested and use protection.
7. The pull-out method (withdrawal) is not an effective form of birth control.
Last but not least, if you take away only one thing from this article, let it be this. Please, please, please do not rely on the pull-out method!
For example, one year of using the pull-out method carries a 22% chance of pregnancy. Ten years of use raises that chance to 92%.
That being said, it’s still one of the most popular forms of contraception in the United States.
Even if someone with a penis withdraws before ejaculation every time they have vaginal intercourse, there’s still no guarantee their partner won’t get pregnant. Pre-cum can contain sperm, which means it can get someone pregnant. Having the perfect pull-out game can’t prevent that.
On that note, thank you for joining me on this sexual health journey. This article can’t cover everything that never made it into the sex ed lesson plans we grew up with, but hopefully you discovered something new today.
If you have any more questions about sex you’d like to see answered in future articles, leave them in the comments. Let’s keep learning together!
Featured image via cottonbro studio on Pexels
