The highest teen pregnancy rates in the U.S. are in low-income areas, and a surprising new study finds that in these communities, teens also have the most difficulty accessing emergency contraception. Researchers found that pharmacists in low-income areas frequently deny 17-year-old girls access to Plan B.

ABC News reports that although pharmacies in low-income areas are just as likely to stock the drug, many pharmacists are misinformed about the law which makes Plan B available for purchase without a prescription by 17-year-olds.

Plan B became accessible for adults to purchase without a prescription in 2006. And in 2009, the FDA lowered the age at which Plan B could be purchased over-the-counter to 17 years of age.

The researchers called over 900 pharmacies in five states, with the caller posing as a 17-year-old girl trying to obtain Plan B over-the-counter after having unprotected sex. Of the pharmacies that claimed to have the pill available, 19 percent said that under no circumstances could the 17-year-old buy the emergency contraception.

But researchers at the Boston Medical Center found that many pharmacists and pharmacy staff members were not made aware of the change in legislation. They attribute possible sources of the problem to the wealth of misinformation about emergency contraception, as well as unclear box labels and advertising.

The study was released in the wake of a survey by the Centers of Disease Control and Prevention, which found that roughly one third of teen moms didn't take birth control because they didn't believe that they could get pregnant.