How late can you get an abortion?

“State rules typically make 20 to 24 weeks the upper limit [of when women can abort a pregnancy], but that’s not really about health concerns and what would be safe versus unsafe,” says Susan Wysocki, a nurse practitioner and board member of the American Sexual Health Association. “Those rules were made by politicians and not physicians. That’s an important thing to recognize.”

The Centers for Disease Control and Prevention reports that more than 600,000 abortions took place in the U.S. in 2013 (the most recent year for which data is available).

Mortality rates for women undergoing legal abortions are extremely low, with the CDC calculating a fatality rate of just 65 deaths per 100,000 legal abortions between 2008 and 2012.

To compare, the CDC reports that there were 17.8 pregnancy-related deaths per 100,000 births in the U.S. between 2009 and 2011. And according to research from the Guttmacher Institute, a first-trimester abortion carries less than a .05 percent risk of major complications requiring hospital care.

But with many state laws limiting when a woman can get an abortion, it’s hard to understand how later-term abortions could actually affect a woman’s health. Is an abortion at 22 weeks just as safe as one at 14 weeks? It depends on various factors. Wysocki breaks things down by trimesters for us below. Here’s what you need to know:

According to a 2013 report by the CDC, 91.6 percent of abortions are performed within the first 13 weeks of pregnancy. And according to Wysocki, “Surgical abortion in the first trimester is one of the safest procedures you can get.”

Although a surgical abortion can be performed as early as a woman’s first missed period, Wysocki says that many doctors like to wait until a woman is five weeks pregnant, and some even prefer to wait up to 12 weeks to do the procedure.

This makes it easier for doctors to ensure they've removed the entire contents of the uterus. “This involves putting a cannula (tube) through the cervix and suctioning the uterine out contents,” she says.

But women also have another option in the first trimester: a medical abortion, which requires taking two pills to induce a miscarriage within the first 10 weeks of gestation. Unlike with surgical abortions, medical abortions become less effective as time goes on.

According to Planned Parenthood, the “abortion pill” is 98 percent effective when taken within the first eight weeks of pregnancy, 96 percent effective between weeks eight and nine, and 93 percent effective from weeks nine to 10.

Planned Parenthood also notes that medical abortions are considered extremely safe. Risks associated with taking these pills are very rare, but can include blood clots, bleeding, infection, or an allergic reaction. And unless you have one of these (highly unlikely) complications, there are no long-term side effects.

Here’s where things get a little bit tricky. Many states restrict abortions between 20 and 24 weeks of gestation, with some exceptions if a woman’s life is in danger. (The Guttmacher Institute has compiled state rules here.) Clearly, there are politics involved in these decisions, but medically, it's worth noting that a fetus likely cannot survive outside the womb until 24 weeks, according to research from The New England Journal of Medicine.

Still, even though an abortion becomes a more complicated procedure around 20 weeks of pregnancy since there’s more that needs to be evacuated, Wysocki says the bottom line is that it is safe to undergo a surgical abortion.

It just might be a little more complicated: "Later in pregnancy, medical instruments may be required to fully remove the contents of the uterus,” Wysocki says, as opposed to the cannula used in the first trimester.

The CDC’s report states that only 7.1 percent of abortions occur between 14 and 20 weeks, with just 1.3 percent happening after 21 weeks of gestation.

According to Wysocki, even if a woman travels to a state with liberal laws (like Nevada or New York), it will generally be very difficult to terminate a pregnancy after 24 weeks of gestation.

But even though it is certainly less common to get an abortion in the third trimester of pregnancy, a woman can safely get one if she has a reason that deems abortion necessary. “One would be that she finds out that there is a serious abnormality with the fetus,” says Wysocki. Another is that there is a health concern for the woman, which could include cardiac issues, uncontrolled diabetes, or uncontrollable hypertension.

A late-term abortion looks very different from one that is performed earlier in the pregnancy because more tissues will have to be removed. In the highly rare case of a 24-week abortion, Wysocki notes that the fetus may be removed in parts to protect the woman’s cervix.

Although there are some risks at this point—for example, an infection can occur if tissue is left behind in the uterus—Wysocki notes that, “there are web sites that list complications of abortions that are untrue. For example, an increased risk of breast cancer and difficulty with future pregnancies is not true. Women should be aware of websites that aim to scare women from making the choice that might be right for them.”

According to Wysocki, the most important thing you can do when deciding to have an abortion is to go to an experienced provider. “The more experience they have, the better they are at it.”