Taking Birth Control While Pregnant: What Happens?

If you've been taking the birth control pill and discover you are pregnant, you may wonder whether this could harm a developing fetus or if there's a chance that it may lead to a miscarriage (sometimes called spontaneous abortion) or stillbirth.

Most research suggests that you need not worry. Some types of birth control may cause complications, but, for the most part, using birth control pills or other hormone delivery devices (such as the Ortho Evra patch or NuvaRing) is relatively safe.

Birth Control Pill and Birth Defects

According to the Food and Drug Administration (FDA), there's no evidence that taking combination birth control pills or progestin-only pills while pregnant will cause harm in any way, either by increasing the risk of birth defects or causing pregnancy complications.

It's important to note that there has not been a lot of research on this subject. This is not because of oversight or lack of interest. Medical ethics would not allow anyone to conduct research that may place a pregnant person or the fetus in harm's way.

Most of the data is derived from epidemiological research comparing people who have used birth control pills during early pregnancy with those who haven't. In this regard, there has been little difference in the number of birth defects, miscarriages, or stillbirths between either group.

The CDC notes that progestins taken in early pregnancy slightly increase the risk of hypospadias (a birth defect where the opening of the urethra is not located at the tip of the penis) in babies assigned male at birth. However, the studies leading to this conclusion are older and were mostly of people taking progestins for infertility or to prevent pregnancy loss and not the low doses of progestins in birth control pills.

If You Think You May Be Pregnant

It's still not recommended that you continue taking birth control if you're pregnant, despite the fact that you've been using birth control medications up until pregnancy is confirmed.

There is no evidence to suggest harm to the fetus.But if you think you may be pregnant, take a pregnancy test to know for sure. If you can't take a pregnancy test for any reason, consider using other forms of contraception (such as condoms or the sponge) until you can.

Pregnancy Risk While On Birth Control

Although abstinence is the only method of birth control that ensures 100% effectiveness for preventing pregnancy, perfect use of contraceptives is nearly 100% effective. Perfect use means that a contraceptive is used correctly every time, while typical use accounts for common human errors, such as forgetting to take a contraceptive pill on time.

With perfect use, the birth control pill is more than 99% successful. With typical use, the birth control pill is about 91% effective. Perfect use of condoms is about 98% effective, while typical use is around 82%.

Long-acting reversible contraceptives (LARCs) such as an intrauterine device (IUD) and permanent contraception methods like tubal ligation (having your tubes tied) are more than 99% effective.

Birth Control and Miscarriage Myths

Most birth control methods don't cause any harm to the fetus when they are used during early pregnancy. There are some common misunderstandings about the difference between birth control and medication abortion pills.

Birth Control Pills

Some people believe that if they continue to take the birth control pill while pregnant, they may have a miscarriage. This is not true, and there has never been any evidence to suggest that. Taking the birth control pill while pregnant doesn't cause a miscarriage.

The hormones in the pill work by stopping ovulation and thickening cervical mucus to prevent sperm from entering the uterus. During early pregnancy, these actions don't contribute to miscarriage or stillbirth.

Emergency Contraception

Another myth is that using emergency contraception (such as Plan B One-Step) while pregnant may cause the spontaneous termination of your pregnancy. This is again not true. These pills have no effect once a fertilized egg has been implanted.

Medication Abortion

There are specific medications that can end a pregnancy if desired. This is a form of medication abortion and is not considered birth control. A medication abortion works through a different method than hormonal birth control. Known as Mifeprex (mifepristone) or RU-486, the abortion pill has been FDA-approved in the United States since 2000.

Risks of Continuing Birth Control

Some birth control methods can cause harm when used during pregnancy. Below is a breakdown of common birth control methods and their risks if used during pregnancy.

COCs or Progestin-Only Pills

Combined estrogen-progestin oral contraceptives (COCs) and progestin-only pills are two different types of birth control pills. COCs contain synthetic forms of estrogen and progesterone, while progestin-only pills contain only synthetic progesterone.

While there's no evidence suggesting birth defects or a miscarriage can occur if you take birth control pills while pregnant, some research suggests an increased risk of wheezing, asthma, and rhinitis in children who were exposed.

IUDs

If you have an IUD and become pregnant, there may be complications. Research suggests that if a person chooses to leave their IUD in during pregnancy, their miscarriage risk will increase to around 40%. Moreover, it can raise the likelihood of preterm birth by some 500%.

With these risks in mind, you should call your healthcare provider immediately to have your IUD removed if you become pregnant and decide to continue the pregnancy. Removing the IUD early in a timely fashion can reduce those risks.

Implants, Shots, and Vaginal Rings

There's no evidence that contraceptive methods like implants, injection shots, and vaginal rings cause birth defects or miscarriages if someone is using them during early pregnancy. These forms of birth control typically use the same types of hormones found in birth control pills.

Barrier Methods

There are no risks when using barrier methods such as condoms, diaphragms, spermicides, cervical caps, and sponges while pregnant. These methods are used to physically prevent sperm from fertilizing an egg and typically do not involve hormones. Using condoms while pregnant can prevent sexually transmitted infections.

A Word From Verywell

Unintended use of birth control pills during early pregnancy is of low risk. If you are pregnant, discuss any medications, supplements, and over-the-counter products with your healthcare provider. You should discontinue taking birth control pills when you discover you are pregnant.