As a general rule of thumb, if a pregnancy question begins with the fact that there was a penis inside of a vagina, the answer is probably, “yes, you could be pregnant.” (Don’t totally freak here, “could be pregnant” is different than “are pregnant.”) The reality is, men and women’s bodies are designed to reproduce. So in order to get them not to, you have to either abstain from sex or rely on the miracles of modern science (ie: birth control). You can’t rely on yoga poses, Coca-Cola douches, or elaborate voodoo ceremonies. The following are 10 scenarios that are NOT reliable ways to protect against an unplanned pregnancy.

You CAN get pregnant if…

A girl is on her period. Sperm can live in the vagina for five to seven days. So even if sex occurred when a girl was on her period (and likely not at a fertile part of the cycle), the little spermies can make themselves at home, and wait around until a girl is fertile.

It’s your first time. All sex is created equal. Meaning, it could be your first or 81^st time and you’re equally as likely to get pregnant.

You had sex standing up or with a girl on top. It doesn’t matter where or in what position you have sex, unless you’re using birth control of some kind, there will be semen in the girl’s vagina. It may seem like most of it drips out, but trust me…there’s still some in there.

You did jumping jacks after sex. Good for you for staying fit!  Unfortunately, jumping jacks aren’t good for anything but getting your heart rate up.

You douched, peed, or took a bath right after having sex. (First of all, you pee out of a different hole…and while it’s always good to pee after sex to prevent urinary tract infections, your pee hole has nothing to do with pregnancy.) And, even if you do douche, take a bath, or flush out your vagina, once semen is up there, the damage is done.

You had sex in a pool, the ocean, or a hot tub. Where you have sex doesn’t matter…pregnancy is still a possibility. Even if there is some water involved, that doesn’t flush out the sperm. (Don’t worry though, if a guy ejaculates in a pool or hot tub—and intercourse wasn’t involved—it’s VERY unlikely that you could get pregnant from that.)

He pulled out. Sex is like basketball, you dribble before you shoot. Even if a guy successfully pulls out, his pre-cum (the stuff that comes out before ejaculation) can get you pregnant.

He came right outside your vagina. You can actually get pregnant even when a guy ejaculates near your vaginal opening. Any vaginal mucus that’s around your vagina can literally serve as a slip n’ slide for sperm to swim into your vagina and all the way up.

You did a lot of drugs, had an eating disorder, your body is unhealthy .Even if your body is unhealthy, your reproductive system is probably working just fine and it’s not worth the risk to have unprotected sex. That being said, if you are suffering from an eating disorder or have addiction problems, you should seek help immediately. 

He’s a stoner, wears tighty whiteys, drinks a lot of Mountain Dew. Ditto. So maybe a guy’s habits are lowering his sperm count from 4 million to 3 million. Even so…he’s still working with A LOT of sperm.

There are no tricks or exceptions when it comes to preventing pregnancy. (If any of these things actually worked, birth control and condom companies would be out of business.) The only way to reliably protect yourself from pregnancy is to be on an ACTUAL method of birth control. And though nothing is 100%, it will significantly reduce your chances of becoming pregnant. Check out our list of birth control methods and make sure you keep yourself protected. Every time.

Have questions about birth control methods or sex myths? Email us!

* image credit: flickr.com

UPDATE: Hi guys—based on the comments below, there are a LOT of questions about whether doing one thing or another could get you pregnant. The bottom line? If you're having sex, you could get pregnant. If you've decided to become sexually active—even if that doesn't mean actually have full on intercourse, but just messing around with your partner—you have to figure out a reliable method of birth control that you use every single time you have sex. And if you're not ready to have sex, that's totally and completely ok, too—it's the only 100% effective method of birth control, so don't write off waiting! In the meantime, if you think you may be pregnant or if you're ready to get on birth control, it's time to see a doctor or health care professional. Need to find one? Use our clinic locator.

Amber Madison has been writing about sex, love, and relationships since college (she went to Tufts University) when she wrote for her school newspaper's sex ed column. Since graduating, she's published two books: Hooking Up: A Girl's All-Out Guide to Sex and Sexuality and Talking Sex With Your Kids and has been quoted in a ton of different media outlets from Seventeen magazine to MTV to NPR. Have a question for Amber? Send us an email!