Pregnancy is possible whenever semen is in or on the vagina. But getting pregnant by wiping is unlikely, especially if the semen is not fresh or only a small amount enters the vagina.
However it happens, if fresh semen enters the vagina of a person who can conceive, pregnancy becomes a possibility.
This article investigates the chances of pregnancy occurring in this way, how to reduce the odds, early signs of pregnancy, and more.
Pregnancy is very unlikely if a person wipes semen on the outside of the vagina — the vulva. For pregnancy to happen, semen has to get inside the vagina.
If a person wipes semen inside the vagina, pregnancy could only happen under the following circumstances:
- Very fresh semen: Sperm can live inside the reproductive tract of the vagina for several days because the environment is warm and moist, and the pH is right for sperm. Outside of the reproductive tract, sperm begin dying immediately.
- A larger amount of semen: While it only takes one sperm to get pregnant, the odds of pregnancy are lower when less semen is in the body.
- The right timing: For pregnancy to happen, sperm need to enter the vagina at or just before ovulation.
Even if all of these circumstances happen, the likelihood of pregnancy remains low. A healthy 30-year-old has about a 20% chance of becoming pregnant during each menstrual cycle that they have sex without using birth control.
The odds of pregnancy resulting from brief contact with semen are even lower.
This is especially true if the semen has been outside of the body for more than a few seconds. During this time, the sperm inside the semen start to die and may be too weak to swim to an egg.
If someone accidentally comes into contact with semen, such as by sitting on a spot where someone has ejaculated, they can try wiping the semen off with a wet cloth. This can help reduce the risk that the sperm will enter the vagina.
If sperm do enter the vagina, and the person wants to prevent pregnancy, the safest strategy is to take Plan B, which is sometimes called the morning-after pill.
In theory, a single sperm is all it takes to get pregnant.
When a small amount of semen comes into contact with the vulva, the odds of even one sperm entering the vagina and making it all the way to the egg are low. The risk is not zero, but it is close to it.
Someone who is very concerned about getting pregnant might worry when clothing or bedding with a semen stain touches their vulva or even after sitting on a toilet seat.
When the semen is old enough not to be wet or visible, there is no risk of pregnancy.
However, if a person ejaculates near the vagina or a person immediately sits so that their vulva touches a surface where someone else has just ejaculated, there is a possibility of pregnancy.
Plan B contains a high dose of hormones to prevent ovulation or, if ovulation occurs, to reduce the chances of the egg implanting in the uterus. This can prevent pregnancy from happening.
Plan B is not an abortion and cannot cause pregnancy loss in a person who is already pregnant.
Anyone who wants to avoid pregnancy after their vagina has come into contact with semen might consider talking to a healthcare provider about Plan B.
To reduce the risk of becoming pregnant or contracting a sexually transmitted infection:
- Use condoms.
- Do not allow a partner to ejaculate in or around the vagina.
- If a partner ejaculates on the body, such as on the chest, wipe the ejaculate off to prevent it from dripping on the vulva.
- Consider the birth control pill if condoms frequently break or a person prefers not to use them.
The only way to completely eliminate the risk of pregnancy is to avoid all sexual contact. This includes mutual masturbation and oral sex.
While the odds of pregnancy resulting from brief contact with sperm are very low, it can still happen, such as if a person were to touch their vagina to masturbate immediately after a partner has ejaculated on their hand.
Many people notice no telltale changes early in pregnancy, so the most reliable way to check is with a pregnancy test — either a storebought kit or a urine or blood test from a doctor.
For the people who do experience them, some early signs can include:
Even when the timing is right, and a lot of very fresh semen enters the vagina when or just before the person ovulates, pregnancy is relatively unlikely.
No studies have assessed the chances of pregnancy after semen is wiped outside or inside of the vagina. However, too many factors naturally interfere for this to be a likely path to pregnancy.
Even so, anyone who is concerned that they are pregnant should contact a doctor or another healthcare provider right away.