Retail chains are limiting the purchase of Plan B pills because of a surge in demand in the wake of the Supreme Court overturning Roe v. Wade and paving the way for states to outright ban or severely restrict medical abortion procedures.

The contraceptive, which consists of a single pill, is available over the counter and costs about $50.

Rite Aid has limited purchases of Plan B to three boxes per customer, a spokesperson told BuzzFeed News, citing increased demand.

Walgreens appeared to have sold out of Plan B pills online as of Tuesday, but a spokesperson said the company has no plans to limit in-store purchases and is working to restock online inventory.

Though CVS initially limited the purchase of emergency contraceptives due to a sharp increase in sales immediately after the Supreme Court ruling, a company spokesperson said demand has since returned to normal and stores would be removing those limits in the next 24 hours.

Walmart did not appear to have any online purchase limits on Plan B as of Tuesday. In a statement, a company spokesperson said many of their products have "online purchase limits in place."

"During times of fluctuating demand, these limits may change," they added.

With Roe overturned, 26 states are expected to ban abortion early in pregnancy or outright, according to the Guttmacher Institute, an abortion rights research and advocacy group that tracks state legislation. But abortion care will continue to be accessible in at least 16 states and the District of Columbia, which have laws in place that protect it as a right. Medication abortions, which have grown to account for more than half of all abortions in the US, are also still an option — though they too face opposition from anti-abortion legislators. For people needing to travel out of state for a procedure, abortion funds can help cover the costs.

Protests have sprung up across the country against the Supreme Court ruling that there is no constitutional right to an abortion. With the procedure expected to be banned or severely restricted in more than a dozen states in the coming weeks and months, demand for medication abortion and birth control has soared, the New York Times reported.