What to Know About Emergency Contraception and Weight — Heavier People Can Still Take It, Expert Says
The nationwide demand for emergency contraception is growing following the Supreme Court's decision last month to overturn Roe v. Wade, the 1973 case that granted women the right to an abortion in every state.
With retailers experiencing a surge in sales of emergency contraceptives like Plan B One-Step, also known as the "morning after" pill, doctors are discussing the potential weight limits that can impact the effectiveness of the pill.
Plan B is an oral pill that can be taken within 72 hours after unprotected sex to prevent pregnancy. According to Planned Parenthood, levonorgestrel — the active ingredient in the emergency contraceptive pills that temporarily delays ovulation — may not be as effective for individuals who weigh more than 165 lbs., according to studies.
A 2015 study published in the Contraception Journal found that the drug began to be less effective for people weighing more than 155 lbs. and reported a pregnancy rate of about 6.4% for people weighing about 176 lbs., compared to just 1.4% for those weighing 155 lbs. or lower.
Another study published in 2016 found that individuals who weighed over 176 lbs. and took Plan B had the same pregnancy rate as those who did not use any emergency contraception at all.
But how can these weight limits apply to various women of different heights and body compositions?
In addition to weight, both studies analyzed an individual's body mass index, or BMI, which is calculated based on a person's height and weight, and that number is used to sort people into four categories: underweight, healthy, overweight or obese.
However, the use of BMI is controversial among healthcare workers as it was developed in the mid-19th century based on problematic racial and societal biases and does not consider a person's ethnicity, gender or body makeup.
Since BMI is not a comprehensive measurement, the weight guidelines in these studies leave a lot of questions unanswered and don't provide clear guidance for people needing emergency contraception.
In 2016, the Food and Drug Administration reported "data are conflicting and too limited to make a definitive conclusion," after the agency completed a review of the effectiveness of emergency contraceptives in women who weigh more than 165 lbs. The FDA, instead, recommended people talk to their health care providers about emergency contraception in advance of needing it.
"There is conflicting data… but I see a lot of people saying that it doesn't work in people who are over 155, or 165, and that's actually not true. It's just that it may not work as effectively," Dr. Heather Irobunda, a New York-based OB-GYN, tells PEOPLE. "So, yes, that's still not where we would want it to be, we want it to work efficaciously for everyone of every size, but just by the mechanism of how the drug works and how it's absorbed in the body, it doesn't work as effectively in people who are larger than those weights."
"What I tell people, it depends on what your situation is," she continues. "So for example, if you have unprotected sex and the only thing you are going to have available is Plan B and you're 180 lbs., I'd recommend taking it because something is better than nothing. And, you know, it's not that it's completely useless."
Irobunda does not recommend people over 155 or 165 lbs taking two Plan B pills in hopes of better efficacy, as there is not enough data to support that it would work. "So until we have that kind of fleshed out in the research, we wouldn't recommend that," she notes.
Dr. Mary Jane Minkin, a board-certified OB/GYN at Yale University School of Medicine, tells PEOPLE that though Plan B pills can be reliable, due to the conflicting data she recommends an intrauterine device (IUD) as a better alternative to emergency contraceptives.
According to Planned Parenthood, an IUD is one of the most effective contraceptives, regardless of an individual's weight, and can prevent pregnancy up to 12 years. It is a small, t-shaped device that is inserted into the uterus by a doctor to provide birth control.
"The advantage of inserting an IUD, of course, is long-acting contraception," Minkin says. "And in this day and age that may not be a crazy idea as far as getting somebody long term contraception and not putting themselves at risk of pregnancy."
"There is a lot of controversy and experts are confused," she adds of Plan B pills and potential weight limits. "But one option that should always be considered is the insertion of an IUD because it works without all the variables."
Additionally, Ella, another type of "morning after" pill, is an option that can be fully effective for individuals who weigh up to 195 lbs. However, it must be prescribed by a doctor or nurse, unlike Plan B, which is available over the counter.
