It has been four years since the federal government lifted the age limit for the morning-after pill, but college students across the country say gaining access to it remains fraught with confusion and difficulty.

Now some colleges think they have found a solution: vending machines stocked with the morning-after pill.

Stanford University unveiled one this month, following in the footsteps of several other colleges, including the University of California, Santa Barbara and the University of California, Davis, which made headlines after it installed a "wellness” machine this year that sells the generic version of Plan B, as well as pregnancy tests, feminine hygiene products, Advil, Claritin and other items.

Parteek Singh, a recent graduate who urged U.C. Davis to install the machine, said he had heard from people at more than 30 schools who are interested in learning how to do the same thing on their campuses.