The US drug regulator approved the first over-the-counter birth control pill in the country, it announced Thursday, dramatically widening access to contraception for women as the United States grapples with reproductive rights.

The medication, Opill, will become available in pharmacies and supermarkets as well as online early next year, the manufacturer Perrigo said in a statement.

Many countries already allow contraceptive pills to be sold over the counter. But in the United States the measure comes as the right to abortion is under renewed assault from conservatives and is now banned in several states.

"Today's approval marks the first time a nonprescription daily oral contraceptive will be an available option for millions of people in the United States," said Patrizia Cavazzoni, director of the Food and Drug Administration's Center for Drug Evaluation and Research in a statement.

"When used as directed, daily oral contraception is safe and is expected to be more effective than currently available nonprescription contraceptive methods in preventing unintended pregnancy."

Almost half of the 6.1 million pregnancies in the United States each year are unintended, the FDA.

Allowing women to access the progestin-only daily contraceptive pill without needing to see a doctor first "may help reduce the number of unintended pregnancies and their potential negative impacts," the FDA statement said.

The pill, produced by the pharmaceutical company HRA Pharma, which was recently acquired by Perrigo, had already been authorized for prescription in the United States for a number of years.