For months, stores across the country have struggled to keep enough baby formula on hand. Manufacturers claim to be operating at full capacity and producing as much formula as possible, but this is insufficient to meet current demand.

Out-of-stock rates for baby formula ranged between 2% and 8% in the first half of 2021, but began to rise sharply last July. According to Datasembly data, the out-of-stock rate increased to 31% between November 2021 and early April 2022.

According to the statistics, that rate increased by 9 percentage points in just three weeks in April, and it now stands at 40%. During the week beginning April 24, more than half of baby formula was completely sold out in six states: Iowa, South Dakota, North Dakota, Missouri, Texas, and Tennessee. Although seven states had 40-50 percent of baby formula products out of stock as of early April, 26 states are now experiencing supply issues.

“This problem has been exacerbated by supply chain issues, product recalls, and historical inflation,” said Datasembly CEO Ben Reich. “Unfortunately, given the category’s unprecedented level of volatility, we expect baby formula to remain one of the most affected products in the market.”

CVS and Walgreens have confirmed that customers will be limited to three toddler and infant formulas per transaction nationwide. “We continue to work diligently with our supplier partners to best meet customer demands,” Walgreens told CNN Business.

A Target spokesperson confirmed that the retailer has limited online purchases of baby formula to four units per customer. According to the company, there is no limit to the number of units that can be purchased in person at Target stores.

Customers shared images on social media of Walmart imposing similar restrictions on baby formula sales, though Walmart did not confirm if the policy was nationwide. Images obtained by CNN Business show empty shelves where baby formula should be, as well as a sign stating that only five units were permitted per customer.

The Food and Drug Administration’s closure of an Abbott Nutrition facility in Sturgis, Michigan, has exacerbated the shortage. Abbott is a major manufacturer of infant formula.

The US Food and Drug Administration recalled three brands of the company’s powdered baby formulas in February due to potential bacterial infections, including Salmonella. The FDA advised parents not to purchase or use certain batches of Similac, Alimentum, and EleCare powdered infant formulas, all manufactured by Abbott.

A former Abbott Nutrition employee filed a whistleblower complaint with the FDA months before the recall, detailing their concerns that the company was concealing safety issues at its Sturgis, Michigan, plant. The formulas made at the facility were recalled after four infants who consumed them became ill with rare infections caused by the Cronobacter sakazakii bacteria. According to the complaint, two infants died.

The recall only affected batches of formulas produced at and distributed from Abbott’s Sturgis, Mich. facility, according to an Abbott spokesperson, and no other products distributed by Abbott have tested positive for Salmonella or other pathogens so far.

Finding standard formula has become difficult for parents, many of whom have described going to extraordinary lengths to obtain even a single can or bottle. Due to the widespread scarcity, specialized formula is even more difficult to find. Parents are traveling to neighboring states to try their luck, and many are pleading for assistance on social media, pleading with strangers to share or even barter any extra supplies they may have.

In a statement released Saturday, Abbott said it is working closely with the FDA to reopen its Michigan plant.

“We are making progress on corrective actions and will take additional steps as we work to address items related to the recent recall. In the meantime, we are working to increase the supply of infant formula by prioritizing infant formula production at our US-based facilities,” Abbott told CNN Business in a statement.