Aunt Vadge: can you get pregnant from semen or urine on a toilet seat?

A banana sits in the middle of a donut with a dollop of cream on its head. It's grinning like mad.

Hey Aunt Vadge, 

If I sat on a toilet seat with fresh semen on it, can I get pregnant? Can sperm move on surfaces and skin?

Also, can you get pregnant from men’s urine on a toilet seat?

Sitting Duck

Dear Sitting Duck,

Great question!

Sperm survival on a toilet seat

Sperm have little tails that allow them to ‘swim’ up the vaginal canal, through your cervix, up into your uterus, and the fallopian tube to your waiting egg.

But they don’t swim like tadpoles; they’re much, much smaller and not that bright, and they can’t move far unless in ideal conditions.

Sperm are not very mobile on dry skin, like a butt cheek, and die within minutes of being exposed to the open air.

This means you are very unlikely to be pregnant unless you happen to be ovulating around that time, and you sat directly on the semen with your vagina, smooshed it around, and some got inside.

Can you get pregnant from sperm on a toilet seat?

Let’s discuss how you might get pregnant from sperm on a toilet seat.

Did the semen touch any part of your vagina, vulva (vaginal lips – labia, clitoris)?

Sperm lasts just minutes in the open air, which means unless the guy ejaculated onto the toilet seat, and then you rubbed your vulva on the toilet seat and the semen straight away, the sperm would have been dead by the time you got to it.

But picture this: how do you smoosh your vagina on a toilet seat long enough and with enough vigour to get the semen into your vagina? I mean, it would be pretty difficult.

You would really have to want to get pregnant to pull this masterful trick off, and even then, it would be much more effective to use your fingers to scoop the sperm into your vagina. (Never do this.)

Even if you did sit on the spermy toilet seat straight away, but only your butt cheek sat in the semen, sperm are not magical teleporters and cannot swim on skin.

But, if you’re still worried, let’s dig a little deeper.

What part of your menstrual cycle were you in?

If you were not close to ovulating (e.g. it was the week of your period, directly after your period or the week before your period, more or less), you are very unlikely to have been fertile, even if you sat directly in the sperm with your vagina and even if you stuffed yourself full of it with your hands. If you’re not ovulating, you can’t get pregnant.

If you don’t know when you ovulate, download a period tracker app for free and start charting. You’ll soon discover when you are most likely to get pregnant and when sitting on sperm on toilet seats will be an ok thing to do, should you want to.

If you think you might have been ovulating and sat directly on the semen with your vagina, you could possibly be pregnant, but again, the level of difficulty is high for this activity.

The special fertile fluid present only around the time you are ovulating makes this swimming easier for sperm and provides a less acidic (more alkaline) environment so that sperm can survive, so there is a very small chance if the planets are aligned.

The normally-acidic vagina proves too tough for the sperm normally, and they will quickly die.

Can you get pregnant from urine on a toilet seat?

You may wonder if sperm pushed out in front of the urine stream out of the urethra and then dripped on a toilet seat, could be a possible source of pregnancy. The answer is that it’s technically possible but highly improbable.

Before we get into whether urine contains sperm, let’s discuss the mechanics of a person with a penis urinating. The penis is pointed away from the person, at the toilet bowl or tree, and the pee comes flying out, typically in a strong, straight line.

In this best-case scenario, sperm will be the first thing ejected from the urethra and most likely NOT land on the toilet seat but flow in the direction of the urine stream.

However, after sex, the first urine may spray in unpredictable directions since there is all sorts of sex gunk in the urethra – vaginal fluids, lube, semen, etc. This gunk can create an uneven stream and possibly land some sperm on the toilet seat.

As we age, the stream of urine can weaken, causing dribbling and possible drips on the toilet seat at first.

The majority of drips on the toilet seat and floor are due to the urine stream weakening at the end of the urination and shaking to clear the final drips. This last bit of urine most likely does not contain any viable sperm.

What the research into the impact of urine on sperm tells us

  • The higher the ammonia content of urine, the less viable sperm was, with most sperm dead after 30 minutes of contact​1​. Meaning, the more concentrated the urine (dehydration, first-morning void), the less sperm was able to survive.
  • However, in another study, 60% of samples were sperm positive after 30 minutes, and after 2 and 4 hours, 70%, and after 5 hours, sperm were no longer detected​2​.
  • The authors did not find any sperm at all in one-third of these samples, indicating not all post-ejaculate urine will contain sperm​2​.
  • Sperm are present in post-ejaculate urine, with more sperm present in infertile men​3​.
  • Men do not have sperm in urine before ejaculating​2​.
  • Sperm is not ‘lost’ in urine between ejaculations, meaning there is no live sperm escaping into the urine randomly.

In conclusion, you’d have to be really trying to get pregnant from a toilet seat!

Warmest regards,
Aunt Vadge  


  1. 1.
    KIM, KIM. Effects of nitrogenous components of urine on sperm motility: an in vitro study. Int J of Andrology. Published online April 1998:29-33. doi:10.1046/j.1365-2605.1998.00083.x
  2. 2.
    Engelbertz F, Korda JB, Engelmann U, Rothschild M, Banaschak S. Longevity of spermatozoa in the post-ejaculatory urine of fertile men. Forensic Science International. Published online January 2010:15-19. doi:10.1016/j.forsciint.2009.10.002
  3. 3.
    Mehta A, Jarow JP, Maples P, Sigman M. Defining the “Normal” Postejaculate Urinalysis. Journal of Andrology. Published online September 10, 2012:917-920. doi:10.2164/jandrol.111.015974
  4. 4.
    APPELL RA, EVANS PR, BLANDY JP. The Effect of Temperature on the Motility and Viability of Sperm. British Journal of Urology. Published online December 1977:751-756. doi:10.1111/j.1464-410x.1977.tb04566.x
  5. 5.
    Ferreira-Poblete A. Advances in Contraception. Published online 1997:83-95. doi:10.1023/a:1006527232605