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The condom broke. You forgot your pill. Or maybe you just got caught up in the heat of the moment. It happens. But now what? It’s time to talk about Plan B.

The lowdown on Plan B

Conception happens when one of your ovaries releases an eggie (aka ovulation) and that eggie meets up with sperm. The morning-after pill works by delaying ovulation or preventing a fertilized egg from implanting into your uterus.

Plan B can provide mega peace of mind if you aren’t planning a pregnancy, but it does have a few downsides. Some people experience bleeding and other side effects after taking Plan B.

Is there an alternative morning-after pill?

Similar to Plan B, ella (ulipristal acetate) also prevents pregnancy if taken up to 5 days after sex. Some reasons to consider ella:

  • It’s 85 percent effective when taken within 5 days of sex.
  • It’s doesn’t become less effective over the course of those 5 days.
  • It’s more effective for folks who weigh 155 to 195 pounds.

Like Plan B, it may cause period irregularities. Your period may show up earlier or later or be heavier, lighter, or spotty.

Here’s everything you need to know about the Plan B morning-after pill.

According to the drug’s package insert, Plan B can cause fluctuations in your period. That means you might get your period at an unexpected time, or it might be longer or shorter than usual. Most women who take Plan B don’t bleed heavily, but it’s possible.

In a 2006 study of 232 women, only 14.7 percent of participants spotted or bled between periods after taking the morning-after pill. While light-to-moderate bleeding is normal, you shouldn’t be bleeding heavily.

There’s not much you can do to prevent bleeding, but you can deal with it just as you would a heavy period.

Be sure to have some period products on hand after you take Plan B, and be prepared for a heavier period than usual. Your cycle should go back to normal the following month.

Some folks think heavy bleeding after taking Plan B is normal, but that might be because they’re confusing Plan B with abortion. Plan B doesn’t trigger abortion or miscarriage.

One more time for the people in the back: Plan B is not the abortion pill. Here’s how Plan B actually works.

Plan B is the name brand of the drug levonorgestrel (aka the morning-after pill). Levonorgestrel is a type of progestin, the synthetic version of the hormone progesterone, which your body produces naturally. Science, baby.

The chemicals in Plan B delay ovulation so sperm never meets your egg. If you’ve already ovulated and your egg is waiting in the queue, Plan B prevents the egg from getting fertilized or stops it from attaching to your uterine wall.

How to take it

Most research shows Plan B has a 52 to 100 percent effectiveness rate. Its success mainly depends on how soon after sex you take it and what stage your menstrual cycle is at.

Plan B One-Step can work up to 120 hours (5 days) after sex, but the sooner you take it, the better. You simply swallow a pill containing 1.5 milligrams of levonorgestrel.

Plan B has no effect on your future fertility, so fear not. When you’re ready to put a bun in the oven, having taken Plan B in the past won’t affect your chances of conceiving.

How often can I take it?

You can take Plan B whenever you need it. But that’s the thing: It should be about momentary need, not an everyday birth control measure. The more you take it, the more out of whack your cycle will be.

Talk to your doctor about alternative birth control options if condoms aren’t your thing. Plan B isn’t as effective in preventing pregnancy as regular methods of birth control.

If you use Plan B on the reg, you may start experiencing irregular periods. The FDA has reported that as many as 31 percent of women have a heavier period after taking it. That’s because progestin disrupts your regular flow. It can take up to a month for your cycle to get back to normal.

Could I be pregnant?

A bit of spotting after Plan B is normal. But that’s not proof you aren’t pregnant. It could also be implantation spotting. That’s when you bleed a bit when a fertilized egg implants to the lining of your uterus. This usually happens 10 to 14 days after conception.

The only way to know for sure if you’re pregnant is to bite the bullet and take a pregnancy test, especially if your period is late. If you’re pregnant and have taken Plan B, it won’t hurt the fetus. To date, there’s no evidence of Plan B leading to fetal development abnormalities.

On top of an irregular period, here are some other possible side effects of Plan B:

  • cramps
  • dizziness
  • nausea
  • vomiting
  • sore boobs
  • fatigue

These effects should disappear after a few days. Plan B isn’t linked with any long-term or dangerous symptoms.

A few factors play into Plan B’s effectiveness. Doctors recommend taking it within 72 hours after a whoopee whoopsy — so you have 3 days to head to the pharmacy and pick it up. If you’re already on birth control, you should keep taking that as you normally would.

Research shows that, while it’s generally effective, Plan B doesn’t have a 100 percent success rate. About 7 out of 8 women who would’ve become preggo won’t conceive if they take Plan B within 3 days after sex. That means 1 out of 8 will get pregnant.

Plan B may not work if you vomit within 2 hours of taking it. Additionally, body size may come into play. It may be less effective in women who have a BMI over 25 or who weigh more than 165 pounds. But that’s doesn’t mean for sure that it won’t work.

Consider an alternative to Plan B

  • If you have a BMI of 25 to 30, ella is a more effective option.
  • If you have a BMI over 30, you may want to discuss the Paragard IUD with your healthcare provider.

Test time

If your period is MIA within 4 weeks of using Plan B, it’s time to take a pregnancy test. If you get a negative result but your period still hasn’t arrived, try another test in 2 weeks to be sure. If it’s negative again, talk to your doctor about why your period may be absent.

If you’re pregnant

If you test positive, have your doctor run a blood test to make sure. If you’re definitely pregnant, it’s time to talk to your gyno about options. You can start prenatal care ASAP if you decide to continue the pregnancy.

If going to a doctor isn’t an option, check out your nearest clinic, like Planned Parenthood. They can help you get the appropriate prenatal care for you and your baby.

If you want to end your pregnancy, you can discuss next steps with your doctor or the folks at Planned Parenthood. Keep in mind that abortion laws vary from state to state. If you’re not sure what your local laws are, check out the Guttmacher Institute’s online platform for up-to-date info on abortion laws nationwide.

Plan B is an over-the-counter medication. You can get it at most pharmacies without a prescription from your doctor. However, getting a prescription or a manufacturer’s coupon ahead of time could save you some cash.

Before taking Plan B

Even though you don’t need a prescription to take Plan B, you should talk to your doctor beforehand if you have any questions. Certain meds may make Plan B less effective. Have a chat with your doctor before taking it if you’re currently on:

Some women are allergic to levonorgestrel. If you are, your doctor can recommend other options.

Keep in mind that emergency contraception won’t protect you from sexually transmitted infections (STIs). Your doctor can offer some great solutions to prevent STIs in the future.

After Plan B

Most women don’t need to see a doctor after taking Plan B. Since the potential side effects wear off within a few days, you should bounce back without issue.

But if you experience the following, it’s time to call your doctor:

  • You vom-bombed within 2 hours of taking Plan B, and you’re not sure if you should take a double dose.
  • Your period hasn’t arrived for more than 4 weeks since you took Plan B.
  • You have very heavy bleeding that’s lasted several days.
  • You’ve been spotting for more than a week since taking it.
  • You have severe lower stomach pain (this may indicate an ectopic pregnancy).
  • You think you’re pregnant and want to talk about how to move forward.

If you catch yourself in a scary spot, don’t be too hard on yourself. Keep calm and head to the pharmacy.

A broken condom, missed pill, or other contraception mishap can happen to anyone. For that reason, many healthcare providers will provide patients with a prescription for Plan B so they can have an emergency pack on hand.

Just remember that Plan B isn’t the abortion pill, nor is it an everyday birth control measure. If you’re taking Plan B frequently, consider other forms of birth control like birth control pills or an intrauterine device (IUD).