ALERT: Leaving Your Birth Control Pills in Your Car Could Get You Pregnant

Have you ever actually read the mini pamphlet that comes with your birth control pills? Didn't think so. Hate to break it to you, but you should. As it turns out, storing your pills the wrong way could mess with their effectiveness.

Most medication should be stored in a dry place at room temperature, ideally somewhere between 68 to 77 degrees. Drugs exposed to temps far outside the range can loose potency. Hormone or protein-based drugs, like oral contraception, may be particularly impacted by "temperature excursion" (i.e. keeping drugs outside of the ideal temperature range).

We chatted with Dr. Margaret Long, OB-GYN, of the Mayo Clinic to find out which situations to avoid—since they could have potentially life-creating results.

In the Bathroom

Bathrooms are a double-whammy no-no. The humidity (which can breakdown the drug) and temperature change from a steamy shower put your pills at risk, according to Dr. Long. Contrary to its name, the medicine cabinet is one of the worst places to store drugs because the moisture and heat from the shower can creep inside. (Kitchen or linen cabinets are much safer spots.) If you like to leave your pack by your toothbrush as a reminder to take your pill every day, store it somewhere else equally reliable instead—like the bowl where you keep your car keys or on your dresser.

On a Plane

Trip to Europe on the horizon? Keep your pills in your carry-on bag. “The temperature control for the [checked] baggage compartment is not the same as for the cabin,” says Dr. Long. “Things may get considerably colder in the baggage compartment than they do where you’re riding.” Just as pills can get overheated and become less effective, if they get too cool, they can also be compromised. It’s better to let them ride first class (lol, I mean economy saver).

In Your Car

The safety of this situation depends on the length of the drive and how hot it is outside. “Birth control pills are not meant to be kept on the dashboard of your car or in your glove compartment,” explains Dr. Long, but generally you can get away with taking them with you in the car if your errand is quick. Treat your pills the way you would a pet. “You’re not supposed to leave pets in cars for very long. If it’s 60 degrees out, you can go get a cup of coffee and it’s not a big deal,” she says. “But, if it’s 98 degrees out, then you can’t ever leave your dog in the car.”

If you have to take your pills with you for a drive, keep them on your person. Don't toss them on the dashboard, where they are exposed to direct sunlight (which can break down the drug), and if your pack ever feels warm to the touch, your pills got too hot. Make sure the AC is pumping for any cross-country road-trips (and, keep the pack up in the front with you, rather than stowed away in the trunk or a glove compartment where temps can soar).

Running Errands

If you are the woman who keeps her pack in the endless pit of her purse so as to be able to take it at the same time every day, no matter where, may we suggest rearranging your schedule to take it at a time you know you'll be at your own place. “Walking to work when it’s hot or commuting when it’s really cold is probably not enough to damage your pills,” Dr. Long explains, offering this caveat: If you have an all-day to-do list to get through (go you!), leave your pills at home.

Bottom line?

If you think your pills were compromised (you won't be able to tell visually), your safest bet is to call your doc for a replacement or use a backup method, like condoms, for the remainder of your pack.

If none of those options are available to you (and you just cannot keep your hands to yourself), keep taking your pills as normal; though the pills may be less effective, they are not toxic, according to Dr. Long.

(But seriously, why not just buy a 99-cent condom? You'll thank me later. )