By month’s end, federal health officials will decide whether to let women buy emergency contraception without a prescription — and if so, if the morning-after pill will be treated more like aspirin off the shelf or like cigarettes. Regardless of how the Food and Drug Administration ends the two-year saga, it isn’t likely to settle the issue. States already are moving to expand access to Plan B, the pill that can prevent pregnancy if taken soon after unprotected sex, amid some competing efforts to restrict it.And if the FDA does allow easier access, the pills probably would come with an age limit — anyone younger than 16 would still need a prescription. So drugstores would have to “card” young customers seeking to prevent pregnancy much as they now check cigarette buyers’ ages.How is unclear. Would morning-after pills sit next to other over-the-counter drugs or condoms? Cash registers could be programmed to block purchase pending an age check. That’s doable: Walgreen’s, the nation’s largest drugstore chain, just last month took that step to prohibit sales to minors of cold medicines containing a sometimes-abused ingredient.Or would the contraceptive be treated like cigarettes, put behind cash registers as a reminder against teenage sales?Or would morning-after pills be sold only “behind the counter,” meaning the pharmacist still must hand them over even though no doctor’s prescription is required?Laws in seven states — Alaska, California, Hawaii, Maine, New Hampshire, New Mexico and Washington — already allow women to buy Plan B that way, with no age restrictions. Massachusetts is set to become the eighth this fall, as lawmakers are expected to override their governor’s veto of nonprescription sales.Whether drugstores even agree to carry nonprescription Plan B will depend largely on whether such steps are required.