What Happens If You Take Birth Control While Pregnant

Because most forms of birth control have a chance of failing, however small that may be, there's always a possibility pregnancy can happen if you're having sex. You may be taking the pill daily or your IUD may be in place, but you could still discover one day that you're pregnant. It would be shocking of course — and frightening. Could there be negative repercussions for your unborn baby because you continued birth control while you were unknowingly pregnant?

If the birth control you were using is a barrier method, such as a condom, sponge, diaphragm, spermicide, Phexxi, or some combination thereof, there's no need to worry. These methods are nonhormonal, and prevent pregnancy by physically blocking sperm from fertilizing the egg or by creating an inhospitable environment for sperm. It's fine, even encouraged, to use a condom during pregnancy if you're concerned about sexually transmitted infections (via Healthline).

Other forms of birth control are based on hormones. These include the pill, Nexplanon (an implant inserted under the skin of the upper arm), a patch worn on the skin, a flexible ring worn inside the vagina, Depo-Provera (an injection given every three months), and one type of IUD, according to Planned Parenthood. There's a second type of IUD that uses copper instead of hormones to prevent pregnancy. 

What should you do if you become pregnant while on hormonal birth control, or while using the IUD? Below, we offer some advice. 

Pregnancy while using hormonal forms of birth control

For all forms of hormonal birth control, the "typical use" failure rate ranges from 0.1% to 7% (per the Centers for Disease Control and Prevention). For the pill specifically, it's 99.7% effective at preventing pregnancy with perfect use, but closer to 91% with typical use (per Medical News Today). The reasons for decreased effectiveness include missing a day, not taking the pill at the same time every day, vomiting due to illness, skipping days between packs, or taking medication that interferes with the pill's effectiveness. 

If you were using the pill or another form of hormonal contraceptive before you discovered your pregnancy, don't panic. There appears to be no link between taking oral contraceptives around the time of conception and abnormalities in the embryo (via Healthline). There had been confusion because research conducted before 2005 suggested that the hormone progestin, taken early in pregnancy, led to an increased risk of a congenital urinary tract defect in males (via JAMA Pediatrics). However, today's consensus is that this isn't true for the modern-day pill, which contains too low a dose of progestin to do harm (per Verywell Health).

Although there's no danger to you, your pregnancy, or your baby from pill use in early pregnancy, you should stop taking it once you confirm conception. Even if you just suspect you're pregnant and haven't yet taken a test, discontinue the pill, and use a barrier method of birth control until you get results. The same is true for any other form of hormonal birth control.

If you become pregnant while using an IUD

The chances of becoming pregnant with an IUD, whether it's the one dependent on hormones or the copper variety, are slim, but it can definitely be problematic. The question is, should the IUD be left in or taken out?

Leaving the IUD in the uterus during pregnancy may lead to a higher chance of miscarriage as well as premature birth. The increase is about 40% and 500%, respectively (via Verywell Health). There's also the risk of developing a condition called chorioamnionitis, which is an infection of the amniotic fluid and the membranes surrounding the developing baby (per Healthline). This condition is one of the causes of premature birth. And then there's the possible link between an IUD left in during pregnancy and placental abruption, which is when the placenta detaches from the uterine wall — a serious situation that can deprive the baby of oxygen and requires emergency care (per the Mayo Clinic).

Finally, there's a higher chance of the pregnancy being ectopic (via Insider). When the fertilized egg implants in a fallopian tube, rather than in the uterus, the pregnancy can be life-threatening.

Considering all these complications, it's recommended that an IUD be removed as soon as possible after a pregnancy is confirmed. Keep in mind that although there's a small risk of miscarriage being caused by removing the IUD, it's generally lower than the risk of leaving the device in place.