Silver Spring, Maryland - US health authorities on Thursday approved the first over-the-counter birth control pill in the country, dramatically widening access to contraception in the United States where abortion rights are increasingly under assault.

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

More than 100 countries already allow contraceptive pills to be sold over the counter. But in the United States, approval comes after the Supreme Court last year scrapped federal abortion protections and the procedure 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."

The agency warned, however, that the pill should not be taken by people who have or have ever had breast cancer.

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

"This moment is a victory for equity, human rights, public health, and evidence-based research – and especially in light of the ongoing attacks on reproductive health and rights, it is a reason to celebrate," said the Free the Pill coalition, a leading advocacy group.

Experts say the decision could be especially significant for teenage girls who may find it harder to get to the doctor, particularly if they want to do it on their own.

"An over-the-counter birth control pill has the potential to transform the way people access contraception, especially those who face the most barriers in our health care system, including LGBTQIA+ folks, people of color, and those working to make ends meet," said Lin-Fan Wang, a family physician serving the LGBTQ community and a Free the Pill member.

In May, an expert advisory committee convened by the FDA unanimously voted in favor of authorizing the sale of Perrigo without a prescription, judging that the benefits outweighed the risks.

The contraceptive pill, taken daily at the same time, prevents a pregnancy during sexual intercourse.