Birth Control and Abortion: How They’re Different

Birth control and an abortion are different. Birth control prevents pregnancy from happening in the first place. An abortion stops an existing pregnancy.

“There’s a huge difference,” says Sophia Yen, MD, a clinical associate professor of pediatrics at Stanford Medical School. While one prevents pregnancy, the other ends it.

The Birth Control Process

Birth control prevents an egg and sperm from connecting and then leading to pregnancy.

There are a few ways it works:

• It stops ovulation, so you don’t release an egg.
• It stops fertilization, so a sperm doesn’t reach and fertilize an egg.
• It stops implantation, so a fertilized egg doesn’t stick to the lining of your uterus.

The birth control pill, for example, stops you from ovulating. It overrides your natural hormones by giving you a steady stream of hormones to prevent ovulation. “If you take it properly, no egg is released, and no conception takes place,” says Tara Scott, MD, a gynecologic surgeon at the Gynecology Institute of Chicago.

Hormonal birth control, like a hormonal IUD, works by thickening your cervical mucus so it’s like cement and sperm can’t get into your uterus. A copper IUD stops sperm from reaching an egg because the copper is toxic, so the sperm avoids your uterus.

“Others work by thinning the lining of your uterus, so if the egg and sperm connect, the embryo can’t stick into the lining,” Yen says. If it can’t stick to the lining, also known as implanting, it can’t get the nutrients it needs to grow.

The Abortion Process

An abortion is a medical procedure. It’s done after three things happen:

• A sperm fertilizes an egg.
• The embryo implants in the lining of your uterus.
• Your body starts making human chorionic gonadotropin (hCG), which is the hormone that pregnancy tests look for.

There are two types of abortion: a surgical abortion and a medical abortion. “To terminate pregnancy, you need to scrape the implanted embryo off or cause the lining of your uterus to shed,” Yen says.

During a surgical abortion, doctors remove the embryo from your uterus. With a medical abortion, you take a pill that makes your uterus contract and shed its lining and the embryo.

Emergency Contraception

Emergency contraception is a type of birth control, not an abortion. “It disrupts ovulation or stops fertilization of the already released egg. It does not cause an abortion of an already fertilized egg,” says Nicole Williams, MD, a gynecologic surgeon at The Gynecology Institute of Chicago.

One type of emergency contraception is pills like Plan B and Ella, which prevent sperm from reaching and fertilizing an egg. You can also use a copper IUD as emergency contraception by preventing the sperm and egg from connecting, fertilizing, and implanting in the uterus.

How Birth Control Affects Your Body

Birth control has some risks and drawbacks, as well as benefits.

“Birth control shuts down your hormone production,” Scott says. It can take a while to produce hormones again after it’s stopped.

Some studies suggest you may have a higher risk of cervical and breast cancer the longer you stay on birth control pills. The estrogen in combined hormonal birth control like the pill, the patch, and the ring, may also increase your risk of breast cancer and blood clots.

On the other hand, the pill, the patch, and the ring, may prevent endometrial, ovarian, and colorectal cancer.

The Effects of an Abortion on Your Body

A surgical abortion has risks that come with having surgery. You may have bleeding, infection, damage to your uterus, or risks that come with anesthesia.

With a medical abortion, risks include an incomplete abortion, bleeding, infection, fever, nausea, vomiting, chills, diarrhea, and headache.

An abortion may also have short-term psychological affects, like mixed emotions, relief, loss, sadness, and guilt. “It can also take your body a month or two to return to your prepregnant state,” Scott says.

Research shows that long-term risks of an abortion are low. Studies also show that having an abortion is unlikely to lead to fertility problems, breast cancer, mental health disorders, or other problems.

But you may have a higher risk of preterm birth if you’ve had two or more abortions before giving birth for the first time or if you become pregnant less than 6 months after having an abortion.

How Much Do They Cost?

It may vary, but the cost of birth control is different from the cost of an abortion. “A surgical abortion can run into the thousands of dollars,” Williams says. “Birth control, if covered by insurance, can be a few dollars a month or even free.”