Before society allowed frank and open discussion about sex, ignorance reigned supreme. Even now, when many of us carry the Internet around in our pocket or purse, some misinformation manages to sneak its way in. This is especially true of birth control. The groundbreaking 1969 "classic" "Everything You Always Wanted to Know About Sex but Were Afraid to Ask" defines birth control as referring to "the hundreds of methods that have been employed to separate the act of copulation from the act of reproduction."

Free Durex Play Vibrating Love Ring worth $10.99 when you spend $30 on Durex condomsYeesh. While antiquated chatter about contraception makes for a laugh, not knowing the facts can do real damage - and that's not funny. With that in mind, here are some of history's most off-the-wall contraceptive misconceptions. (For some background reading on contraception, read The Ultimate Guide to Safe Sex.)

Jumping Up and Down

Everyone has heard this old wives' tale. The premise is that if a woman leaps out of bed immediately after sex (which is totally what she'll want to be doing, right?) and jumps up and down vigorously, the sperm will be confused and no pregnancy will occur. This has been debunked in plenty of books (not to mention an episode of "Roseanne").

But where did it start? In fact, this myth may be as old as medicine itself. Hippocrates - the man for whom the Hippocratic Oath is named - asserted that a woman should "make violent movements with her body after intercourse to prevent conception from reaching the uterus." Honest, that's taken directly from "The Hippocratic Corpus", the classic medical reference written by Hippocrates and his students. This is why even the best 2,000-year-old books should probably not be used as sex manuals. (For related reading, check out Why We Need Sex Ed.)

Birth-Control Pills Lead to Infertility

This rumor may have begun because women sometimes take birth control pills until they are in their 30s, an age at which conception becomes more difficult. Since the pill's introduction in 1960, rumors of side effects like weight gain, hair loss, pimples, and permanent infertility have been persistent.

The good news is, the reality is not nearly as ironic. Dr. Vanessa Cullins, writer of Planned Parenthood's long-time column "Ask Dr Cullins," assures us that there is no evidence to suggest a link between birth control pills and long-term infertility. She goes on to say that birth-control pills are among the most rigorously tested drugs on the planet and, when taken properly, are considered very safe. Birth control pills: Take 'em if ya got 'em!

Timing Is Everything!

In her book "Dr Ruth's Guide to Safer Sex," Dr. Ruth Westheimer said she was "startled" to learn how many teenagers believed they couldn't get pregnant their first time, and that the hymen served as a barrier to conception.

The reality? No such luck; the first time really can be the charm. The truth is that even if there is bleeding or discomfort, this does not interfere with the merry dance of sperm and egg. And yes, that's even true when a woman is menstruating.

Condoms: Tighter Is Better

If snugness provides protection, a latex stranglehold must provide super-duper protection, right? Nope. A too-tight condom is much more likely to tear during intercourse. Both Trojan and Durex condom companies say that condoms should fit snugly and comfortably when applied, while leaving ample room at the tip.

While it might be fun for the fellas to rip through a condom (like Bruce Banner becoming the Incredible Hulk, right?), a torn condom is useless at doing everything you need a condom to do. Try a few different brands, even measure if you have to, but make sure it fits. Condoms are something you never want to stretch past the breaking point.

What Goes Up ...

It's been surmised for centuries that gravity could be used to prohibit conception. Tenth century Persians believed that if both partners remained standing during sex, no conception would occur. Ancient Egyptians believed that sex in the river could not result in offspring. Many American youths still believe that woman-on-top sex is less likely to result in pregnancy.

In reality, if you try either one of these you're as likely to end up with a baby as you are with a back-ache or algae infection. If you are not yet wise in the ways of the penis, you may not realized just how fast and eager those little swimmers are when they exit the male body. (Uncover more mysteries of the penis in 10 Things You Don't Know About Penises.)

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Coitus Interruptus

Coitus interruptus is not just slang for parents, kids, or nosy neighbors barging in on the tender act of love. It's also the formal name for the withdrawal method, also known as "pulling out." This unsatisfying birth-control method involves abrupt, pre-ejaculation extraction of the penis from the vagina. And, yest, it is every bit as romantic as it sounds.

Surprisingly, Planned Parenthood tells us that when performed correctly every time, coitus interruptus will result in pregnancy about four out of every 100 times. Those sound like good odds until we note that very few men can do this correctly 100 percent of the time. Ultimately, it equals less satisfying sex - not to mention less reliability than every other legitimate birth control method. Also, pre-ejaculate does contain some sperm, although not as much as the full payload.

Just Like a Condom!

The idea that the same thing you'd use to cover that last portion of mashed potatoes might be used to protect you from pregnancy is a bit of a stretch. Even so, everything from sandwich bags to chocolate bar wrappers have been used for this purpose.

The bad news is, trying to MacGuyver yourself a condom is not just bad contraception - it leaves both parties open to infections, pain, lack of sensation, and the sort of injuries you'd be really embarrassed to explain to an emergency room nurse. Seriously, condoms are a couple of dollars and you can buy them anywhere. Or just stop a random person in the street and ask for one; chances are, somebody will help you out. Just try to look non-threatening when you do this.

Coca-Cola to the Rescue

The aforementioned "Everything You Always Wanted to Know About Sex" explains the various rumors that surround douching as a form of birth control. The book was released in 1969, and claimed that douching was the most commonly used form of birth control at the time. Lysol, chlorophyll, and even that blue liquid barbers put combs in were used immediately after intercourse in the hope of preventing pregnancy.

Free Durex Play Vibrating Love Ring worth $10.99 when you spend $30 on Durex condomsSorry, folks. We now know that douching cannot rid the body of all of the 300 million sperm that are released during one encounter. Not even close. Through the '60s and '70s, the contraceptive douche of choice was a Coca-Cola. Back then, it came in 10-ounce glass bottles you could shake up and ... ahem ... insert to kill sperm. Like other douching liquids, it was ineffective and had nasty side effects. We now also know that sugar in the underpants zone is the quickest road to a yeast infection. Yikes! (Learn more about this area in 10 Things You Don't Know About Vaginas.)

But I Didn't…

No orgasm, no pregnancy? Yes, there are people who believe a woman cannot conceive if she didn't have an orgasm during sex. Surprisingly, there is some physiological basis for this. During orgasm, contractions can give the sperm a little boost toward the cervix.

The reality is that even if the sex is worse than average, more than a few swimmers can - and often do - find the cervix. It's not that far away. So, if you're thinking of passing on the orgasm in the hope of preventing pregnancy, please, enjoy yourself. This form of contraception just isn't good enough to merit the sacrifice.

In sex, as in everything, good information is the key to making smart choices. Starting a family need not be an accident, especially now that so much safe, effective contraception is available.