TRENTON, N.J. - Princeton University has started subsidizing the cost of birth-control pills for its students amid the skyrocketing cost of the drugs on college campuses.

Since Saturday, students going to the university's health center have been able to get a one month's supply of generic birth control pills for $6, versus the $15 they were paying since March, according to Princeton spokeswoman Cass Cliatt.

To cover the difference, Princeton is dipping into a private discretionary fund. Early estimates, according to Cliatt, place the cost of the subsidies at about $69,000 a year.

"Many Princeton students voiced their concerns about their ability to gain access to affordable oral contraception," Cliatt said.

Prices for oral contraceptives, or birth-control pills, doubled and tripled at some student health centers across the country as a result of a complex change in a Medicaid rebate law that essentially ended an incentive for drug companies to provide deep discounts to colleges.

At Princeton, brand-name birth control pills used to cost $6. When the law changed in January, the Princeton pharmacy switched to generic birth control pills, which cost students $15.

The university subsidy, which went into effect Saturday, now allows students to purchase generic oral contraception for $6 a month.

"There's an overwhelming majority of students who favor the subsidy because it's such an important health issue," said Josh Weinstein, vice president of Undergraduate Student Government at Princeton.

Princeton's move to subsidize the cost of birth control is unusual because many colleges and universities don't have the same financial resources, according to Mary Hoban, an official with the Baltimore-based American College Health Association.

"It's pretty new and it's going to be pretty unusual," Hoban said.

At Harvard, the university in a way subsidizes birth control as part of a system in which students pay a mandatory health fee, and then a $5 co-pay for prescription drugs at the health center, said Dr. David Rosenthal, director of the Harvard University Health Services.

Rep. Joseph Crowley, D-N.Y., who is sponsoring a bill in the U.S. House to restore the old Medicaid rules, noted that many college-age women across the country aren't able to go to a school with the same resources as Princeton.

"What about institutions that don't have kitties, that don't have funds, that don't have endowments? What are their options?" Crowley said.