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Not every sperm is a “Demon Sperm.” But they do need to get lost if you don’t want to get pregnant.

Spermicide condoms can knock those swimmers out with a one-two punch of latex to keep them from escaping, and a chemical (the spermicide) to slow down any that do.

Most spermicide condoms are coated with nonoxynol-9. This chemical is also an ingredient in shaving cream, Ben-Gay, and poison ivy lotions. (There are good jokes in at least two of those things, but let’s stay focused.)

Spermicides like nonoxynol-9 are a form of birth control that immobilizes and slows down sperm before they get to the cervix. (No killing sperm, here. Spermicide technically doesn’t kill sperm!)

Since sperm have to swim all the way to the fallopian tubes to meet up with the egg, spermicide is really a bad day at the beach for sperm.

It can be used alone or with other contraceptives. Spermicides also come in a variety of forms including:

  • condoms
  • gels
  • films
  • foams
  • creams
  • vaginal suppositories

Spermicide alone is a pretty unimpressive contraceptive. According to the CDC, it’s only about 28 percent effective for people who use it as birth control.

Combining spermicide with condoms (which are up to 98 percent effective), would seem to offer at least some extra protection if a condom breaks or is used improperly.

But research shows that spermicide condoms are no more effective in preventing pregnancy than condoms that aren’t coated with spermicide.

Spermicide may also be worse than useless in protecting against STIs. Research shows that spermicide-coated condoms (like spermicide used alone) may actually increase the possibility of contracting HIV by irritating the walls of the vagina or rectum, which could make infection more likely.

This risk goes up if you use spermicide condoms several times a day, or for several days in a row.

You might say that spermicide condoms are, at best, a mixed bag.

On the plus side…

  • They’re affordable, portable contraceptives that are available without a prescription.
  • Used properly, they can protect against unwanted pregnancy.
  • If a sperm manages to do a Super Mario and makes it to an egg, there’s no evidence that spermicide will cause birth defects.
  • Spermicide won’t show up in breast milk, either.

The negatives…

  • Spermicide condoms cost more than regular condoms.
  • They don’t last as long, and don’t come with as much spermicide as other spermicide products.
  • They don’t protect against pregnancy or STIs better than regular condoms.
  • Spermicide condoms might make transmission of HIV more likely, not less, by irritating the penis and vagina.
  • Nonoxynol-9 can also cause allergic reactions such as itching, redness, and swelling. Oh, and urinary tract infections are a risk, too.

Because of the negative side effects of spermicide condoms, many doctors don’t recommend you use them over regular condoms. If you experience any ill side effects of using spermicide condoms, you could try another brand. Or, use another type of birth control and protection.

The most obvious alternative is to use a condom (male or female) that doesn’t include spermicide. Female birth control pills are even more effective in preventing pregnancy (99 percent if taken properly), but they don’t prevent STIs.

Other options include:

Less effective, but still better than riding bareback, are:

Used properly, condoms are an affordable and effective form of birth control, whether they include spermicide or not.

Spermicide condoms seem like a good idea because they protect against unwanted pregnancy in two different ways. But there’s no evidence that they’re any better at preventing a baby bump.

Spermicide condoms also can cause side effects that you don’t have to worry about with regular condoms.