Following the Supreme Court’s decision last month to overturn Roe v. Wade and to end the constitutional right to abortion, the demand for emergency contraceptives has increased in many areas. Some people have been quick to stock up on morning-after pills for fear of not being able to access an abortion or because they fear possible future restrictions on birth control, as the New York Times recently reported.
Emergency contraceptives, which prevent pregnancy from occurring in the first place, are different from abortion pills. However, it is useful to understand how the two types of drugs work and when they are used, experts say, especially when demand increases. Reproductive health company Stix told the New York Times sales of his morning-after pill increased 600% within a day of the Supreme Court ruling.
“A lot of the confusion around emergency contraception and how it works is probably because we do such a poor job of teaching reproductive health,” says Beverly Gray, OB-GYN at Duke Health in North Carolina. and founder of the Duke Reproductive Health Advocacy and Equity Mobilization Team. “[Our] patients are experts in their own lives on what birth control methods will work for them.
Emergency contraceptives can be taken up to five days after unprotected sex, the length of time sperm can live in the reproductive system. They delay or prevent ovulation, the stage of the menstrual cycle in which an egg is released from an ovary, which in turn stops the fusion of sperm and egg.
“If the egg is released a few days later or not at all during this cycle, the sperm and egg cannot unite,” says Gray.
[Related: Why doctors still don’t understand the side effects of hormonal birth control]
Emergency contraceptives don’t work once a day the fertilized egg is implanted in the womb. In other words, they don’t interfere with ongoing pregnancies, Gray says.
Some morning after pills contain levonorgestrel, which belongs to a group of medicines called progestins which mimic the natural hormone progesterone. Plan B One-Step, which has a shelf life of about four years, is an example of a levonorgestrel pill. This compound is also used in lower doses for some other forms of birth control, writes Aldene Zeno, obstetrician-gynecologist at Keck Medicine at the University of Southern California, in an email.
Levonorgestrel suppresses flare-up luteinizing hormone which usually triggers ovulation. Additionally, the drug thickens the mucus in the reproductive tract to prevent sperm and egg from moving towards each other and changes the lining of the uterus to prevent implantation if the sperm and egg egg meet.
“Biologically, as humans, we are wired to carry one pregnancy at a time. That pregnancy can be a singleton or multiples like twins, but either way, once a person becomes pregnant, their body triggers processes, many of which are driven by progesterone, to prevent another pregnancy from occurring,” says Zeno. “Plan B mimics this mechanism of to prevent pregnancy, however, it is not effective in terminating an existing pregnancy.
One of the advantages of levonorgestrel emergency contraceptives is that they are available without a prescription. However, they doesn’t work as well in people who weigh more than 165 pounds. The sooner the pills are taken after unprotected sex, ideally within 72 hours, the more effective they are and reduce the chance of pregnancy by 75-89%.
Another type of emergency contraceptive pill is ulipristal, sold under the brand name Ella. This is more efficient than levonorgestrel pills and can be taken up to five days after unprotected sex. If taken within this window, it reduces the chance of pregnancy by 85%, according to Planned Parenthood. However, ulipristal may not work as well in people over 195 pounds and is only available by prescription.
In addition to blocking the surge of luteinizing hormone, ulipristal can also disrupt ovulation later in a person’s menstrual cycle by preventing follicles – fluid-filled sacs in the ovaries that contain eggs – from developing. to break up. Compared to levonorgestrel pills, Gray says, “it works a little better if you’re just around the time of ovulation, if the luteinizing hormone surge is already happening.”
Another even more effective emergency contraceptive option is to get a copper IUD implanted within five days of unprotected sex, Gray says. If inserted within this time frame, IUDs reduce the chance of pregnancy by 99.9%. Copper has spermicidal properties and can also prevent implantation, but does not disrupt an already established pregnancy. It also works regardless of a person’s weight. Hormonal IUDs that release levonorgestrel like Mirena can also be used for emergency contraception. A study published last year in the New England Journal of Medicine indicates that the release of levonorgestrel Hormonal IUDs are equivalent in effectiveness to the copper IUD for emergency contraception.
While emergency contraceptives prevent pregnancy, abortion pills are used to terminate an existing pregnancy. A medical abortion can be done up to about 11 weeks of pregnancy and requires taking two medications. The first pill, called mifepristone, blocks the hormone progesterone, which is needed for pregnancy growth. The second drug, misoprostol, causes cramping and bleeding to help the uterus empty. These drugs are also used to treat miscarriages.
“All birth control methods have failure rates, including emergency contraception,” says Zeno. This is one of the reasons why abortion will remain an important safety net. “Abortion care is an integral part of women’s health care.”
[Related: What science tells us about abortion bans]
Since the Supreme Court ruling, Gray and her colleagues have seen demand for long-acting forms of contraception skyrocket. “We’re just seeing higher volume than we’ve ever seen,” she says. For people who aren’t already using a very effective form of birth control like an IUD, it’s not a bad idea to have the morning after pill handy. “I think it’s good to be prepared,” Gray says.
Still, Zeno advises against stockpiling emergency contraception in response to the ruling.
“There are equity concerns around access to the ‘morning after pill,'” she said, noting that emergency contraception is less available in low-income and predominantly Latin and Black neighborhoods. “If those with the means buy most of the supply in their area, they are disenfranchising those who might otherwise need it and who already have limited resources.”
Ensuring birth control is widely available leads to fewer unwanted pregnancies and abortions, she added. “Access to emergency contraception is important,” Zeno said. “However, instead of stocking up on emergency contraception, I advocate long-acting reversible methods of contraception.” These include the IUD and implants such as Nexplanon.
To help you determine which birth control method is best for you, Gray recommends consulting the Birth Control Support Network. Bedside and the American College of Obstetricians and Gynecologists website.