Abstinence and outercourse are VERY effective at preventing pregnancy — but only if you don’t slip up and have unprotected vaginal sex or get any semen in the vagina.
How effective is abstinence?
If you never get semen (cum) on the vulva or in the vagina, pregnancy can’t happen. Abstinence is 100% effective as long as you’re actually abstinent. But if you do have unprotected vaginal sex — even just one time — pregnancy can happen.
Nobody’s perfect, and sometimes people plan on being abstinent but end up having sex. That’s why it’s a good idea to keep condoms around, just in case. Being prepared and having protection doesn’t mean you’re definitely going to have sex — it means you’re responsible and taking care of your health.
How effective is outercourse?
Outercourse activities are 100% effective at preventing pregnancy: kissing, massage, masturbation, dry humping with clothes on, anal sex, and oral sex can’t cause pregnancy.
That said, pregnancy can happen, rarely, even if you don’t actually have vaginal sex. If semen (cum) accidentally gets on a vulva, sperm can swim up into the vagina and fertilize an egg.
There are a few ways this can happen:
Cum gets on the vulva. It can accidentally drip or be wiped onto the vulva.
There’s wet semen on someone’s fingers and/or sex toys, and they touch the vulva or go in the vagina.
Semen drips out of the anus and into the vulva after anal sex.
Bottom line: if you’re trying to avoid pregnancy, don’t get semen (cum) on the vulva or in the vagina. Pre-ejaculate (precum) can also have some sperm in it, so keep pre-cum away from the vulva and vagina, too.
Do abstinence and outercourse protect against STDs?
Abstinence is 100% effective at preventing the spread of sexually transmitted infections. If you don’t have any kind of sexual contact with another person, you can’t get STDs.
Sexually transmitted infections can be spread by touching genitals and sharing sexual fluids (like semen, pre-cum, and vaginal moisture). So there are a few ways outercourse can put you at risk for sexually transmitted infections:
Oral sex and anal sex spread most of the same STDs as vaginal sex. Use barriers like condoms and dental dams to help protect each other.
Swapping sexual fluids (semen, pre-cum, and vaginal fluids) (like if you have semen on your hand and touch your partner’s genitals) can transmit STDs.
Wearing underwear makes dry humping safer, but it may not prevent all skin-to-skin genital contact or keep sexual fluids away. And some STDs can live on areas that underwear doesn’t always cover (like your upper thighs or butt cheeks).
If you’re going to have outercourse but you don’t want to worry about STDs, avoid all skin-to-skin genital contact, and keep sexual fluids away from each other.
If you’re doing any of these activities that can pass STDs, get tested regularly. You can also use condoms and dental dams to reduce your risk of STDs if you have oral and/or anal sex — this is called “safer sex.”