 So it wasn't included in the study, but Cato says it's unlikely to have made a big difference considering that those options are still really expensive and out of reach for low-income people. Take Opal, which is the FDA's approved birth control pill that you can get over the counter. There's no need for a prescription. It runs about $20 a month. But if you have insurance, even Medicaid, you can get prescription birth control covered for free. So it's not likely to have a big impact.