Though you may be taking birth control, it’s still possible to become pregnant in certain situations. Dawn Yanek — mom, author, and founder of Momsanity — highlights how you may get pregnant despite using methods of birth control.

Call it nature, call it the biological imperative, call it irony: The truth is that your body generally wants to get pregnant, even if it’s not exactly on your to-do list.

The species wants to survive, and we are Mother Nature’s pawns. (Of course, when we actually want to get pregnant, it’s not always that easy, but that’s a whole other story for a whole other article.)

Anyway, we often spend most of our younger reproductive years trying not to get pregnant, and we’re generally pretty successful. We’re informed, we know which birth control works best for us, and we’re aware of the common problems.

But here’s the thing: What you think you know about birth control may not necessarily be accurate. And a “surprise” pregnancy can be easier to come by than you may think.

Believe it or not, here are some ways you can still get pregnant:

Many breastfeeding moms don’t get their periods while nursing. This leads them to believe they’re not ovulating and, therefore, can’t get pregnant. Nope!

Using breastfeeding as birth control is called the lactational amenorrhea method (LAM). It often works when your baby is under 6 months old, you’re exclusively breastfeeding, and you haven’t yet gotten your first postpartum period.

Here’s the thing: We usually ovulate 2 weeks before we get our first period. So you can absolutely still get pregnant because your body can kick back into baby-making gear at any time.

Plus, bouts of stress can decrease your milk supply, which in turn can increase fertility hormones.

There’s a big warning label on every pill packet that says taking antibiotics may lessen the effectiveness of the birth control pill, but many people don’t read the fine print.

The only antibiotics that can interfere with the pill are rifampin and rifabutin. Rifampin is prescribed to treat tuberculosis, and rifabutin is prescribed to treat MAC disease, a bacterial infection.

Scientists say there isn’t an issue when using other antibiotics. Their take is that pregnancy may occur when taking other antibiotics because people may skip a pill or two when they’re not feeling well, or their bodies may not be able to absorb the hormones properly if they’re vomiting or have diarrhea.

All that said, I know a decent number of moms who have gotten pregnant while taking antibiotics, so you probably don’t want to risk it.

If you swallow the pill but vomit it back up or send it out quickly with diarrhea, it can reduce its effectiveness — your body doesn’t have a chance to absorb it. So it’s like you didn’t take the pill at all.

While you have a less than 1% chance of getting pregnant by someone who’s had a vasectomy, you might have a much larger chance if you don’t wait until your partner’s been tested to see whether it worked.

Your partner’s sperm should be checked after 15 to 20 ejaculations, or about 3 months after the procedure. Make sure to use other protection until you get the OK from your doctor.

IUDs have a success rate of over 99%, so pregnancy is very uncommon — but not impossible.

One way to make sure your IUD remains effective is to see your doctor 1 month after IUD insertion. Have them make sure the IUD is still positioned correctly in your uterus.

Also keep this in mind: With hormone-based IUDs like Mirena, some people don’t get their periods. But if you experience any traditional pregnancy symptoms like breast tenderness, morning sickness, or extreme fatigue, you should take a pregnancy test and call your doctor.

IUD pregnancies carry a higher risk of miscarriage and ectopic pregnancy, so you’ll want to talk with your doctor immediately.

They seem pretty easy to use, and hey, we all tested them out on bananas in health class back in the day. You may think, “What could go wrong?”

Here’s the short list of what can reduce a condom’s effectiveness:

  • using condoms with oil-based lubricants, like petroleum jelly or coconut oil, which erode latex
  • using expired condoms (yes, they have an expiration date)
  • using condoms that have been exposed to extreme temperatures (don’t leave them in the glove compartment of your car in the cold of winter or heat of summer)
  • accidentally ripping them with teeth, scissors, or a nail when opening the packet
  • not leaving enough room at the tip
  • not pulling out (with the condom on, of course) soon enough after sex

Maybe that’s not such a short list after all.

Just because you’ve had infertility issues doesn’t necessarily mean you can never get pregnant.

According to a 2023 review, 20% of people who had given birth following assisted reproductive treatments later conceived naturally.

While researchers aren’t quite sure why this happens, some suggest that pregnancy kicks the body into gear and can also suppress the effects of conditions like endometriosis, allowing conception to happen more easily.

Plus, pregnancy-related stress is at an all-time low since it’s the last thing on your mind until — surprise!

If you’re not quite ready for a surprise, make sure to take the proper precautions.

Oh, yes, you read that right: You can get pregnant when you’re already pregnant.

It’s called superfetation, and it’s very, very, very rare. It happens when you’re pregnant and your ovary releases an egg a few weeks into your pregnancy, and then you have sex at just the right (or wrong!) time.

This is so rare (only around 10 known cases) that the majority of women, myself included, won’t take precautions against it, but you should still know that it’s a thing.

Read on to learn some frequently asked questions.

What is the possibility of getting pregnant while on birth control?

The possibility of pregnancy on birth control depends on the method used and how well you follow instructions.

The pill is over 99% effective with perfect use. However, if you vomit or have diarrhea, the pill may not be effective if it has left your system.

What are the signs of pregnancy on birth control?

Early signs include cramping and spotting in the first few weeks, missing a period, increased body temperature, and fatigue. You may also have a faster heart rate, tender breasts, and mood changes. Urinating more or having incontinence can also happen, as well as bloating and nausea, otherwise known as morning sickness.

What causes birth control to fail?

Causes of failure include incorrect use, like skipping doses, or having vomiting and diarrhea, which may cause the medication to leave your system too early.

Birth control methods aren’t 100% effective, so even if you follow all instructions, there’s a possibility you may still become pregnant.

How long should you be off birth control before trying for a baby?

You can start right away, but some people choose to wait until after their first period. It may take some time to regain fertility, depending on the birth control you were on and how long you used it for.

Everyone’s body is different, so it’s best to start when you feel comfortable and ready.

Birth control isn’t 100% effective, even if you take it according to instructions in what’s known as “perfect use.” Many birth control methods are at least 99% effective, though, with typical use, which accounts for how most people generally use them.

However, there are certain things you can do and particular things to be aware of so you can increase the effectiveness of your birth control method and avoid common mistakes people make.

Dawn Yanek lives in New York City with her husband and their two very sweet, slightly crazy kids. Before becoming a mom, she was a magazine editor who regularly appeared on TV to discuss celebrity news, fashion, relationships, and pop culture. These days, she writes about the very real, relatable, and practical sides of parenting at Momsanity.com. Her newest baby is the book “107 Things I Wish I Had Known with My First Baby: Essential Tips for the First 3 Months”. You can also find her on Facebookand Pinterest.