Pharmacies may misinform teens about whether they are allowed to buy emergency contraception, which can prevent pregnancy after sex, a new study finds.

Such misinformation is more commonly given by pharmacies in low-income neighborhoods, the study showed.

The researchers called 943 commercial pharmacies in five states. The caller posed as a 17-year-old girl seeking emergency contraception after unprotected sex. Under Food and Drug Administration rules, the emergency contraception drug called Plan B may be sold over the counter (without a prescription) to women ages 17 and older (those ages 16 and younger need a prescription).

But of the pharmacies who said they had emergency contraception available that day, 19 percent said the 17-year-old caller could not buy the emergency contraception under any circumstances. The pharmacies who responded this way usually hung up the phone quickly.

“We were really surprised that so many pharmacies actually ended the conversation at that point,” said study researcher Dr. Tracey Wilkinson, a pediatrician at Boston Medical Center.

The misinformation was more common in poor neighborhoods: 23.7 percent of pharmacies in low-income neighborhoods said the teenage caller could not obtain emergency contraception at all, compared with 14.6 percent in other neighborhoods.

In addition, just under half (44 percent) of pharmacies surveyed gave the incorrect age at which a teenager can obtain emergency contraception without a prescription. Most who got it wrong said a person needed to be older than 17 to obtain emergency contraception. In low-income neighborhoods, about 50 percent of pharmacies gave the incorrect age, compared to about 37 percent in other neighborhoods.

The findings suggest that access to emergency contraception is particularly difficult for young women living in low-income areas — areas that also have higher rates of teen pregnancy, Wilkinson said.

While access to Plan B isn’t the only factor that affects teen pregnancy rates, “knowing that teen pregnancy rates are higher in low-income neighborhoods makes this disparity an even bigger problem,” Wilkinson said.

The researchers noted their results are based on calls to pharmacies and not in-person visits, which may have yielded different responses. But adolescents may call pharmacies beforehand, and may be discouraged from going to a pharmacy in person if they receive incorrect information about emergency contraception, Wilkinson said.

Pass it on: Women ages 17 and up can buy Plan B without a prescription.

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