U.S. Senator Maggie Hassan flagged the issue to major tampon manufacturers Procter & Gamble, Edgewell Personal Care, and Kimberly-Clark in a letter earlier this week, asking how they plan to address reports of diminished supply and price gouging by third-party resellers. 

“In recent days I have seen troubling reports about low supplies and even empty shelves of tampons—as well as concerning indications that instead of increasing supply, companies have increased tampon prices,” Sen. Hassan wrote. “While the tampon shortage is part of a larger supply chain issue, price gouging essential products is an unacceptable response.”

Retailers told Fortune that they are struggling with tampon stocking issues, confirming months of complaints from consumers struggling to locate certain period products in stores.

Walgreens spokesperson Kris Lathan told Fortune that the pharmacy store chain may have a limited selection of brands to choose from. 

“Similar to other retailers, we are experiencing some temporary brand-specific tampon shortages in certain geographies,” she said. “While we will continue to have products at (sic) shelf and online, it may only be in specific brands while we navigate the supply disruption.”

Target also acknowledged it’s experiencing a shortage. The big-box retailer told Fortune it has a wide variety of feminine care products but is working to secure more inventory from tampon manufacturers where product shipments have been limited.

A looming tampon shortage was first reported by Time last week, but organizations that provide free menstrual health products to those in need told Fortune that they’ve been seeing their inventory and donations dwindle for months. 

“Because we are receiving these as donations, we often are the first ones that need to have a pause on what we receive,” said Meghan Freebeck, the founder of Simply The Basics, the first national hygiene bank which provides personal care products at no cost. “If this goes on for a few more months at the same rate, we will run out. We will be out of stock.”

Why is it so much harder to get tampons? 

Major tampon manufacturers say that the tampon shortage has been caused by COVID workforce shortfalls and manufacturing holdups. 

In a recent earnings call, Andre Schulten the chief financial officer of major tampon manufacturer Procter & Gamble said it had been “costly and highly volatile” to source the raw materials needed to produce tampons, such as cotton, rayon, and plastic. 

When reached for comment about the senator’s letter, Procter & Gamble called the short supply a “temporary situation.”

“The Tampax team is producing tampons 24/7 to meet the increased demand for our products,” a company spokesperson said. “We are working with our retail partners to maximize availability, which has significantly increased over the last several months.”

A spokesperson for Edgewell Personal Care, which makes Playtex tampons, said the production and inventory of its products have been “impacted due to extensive workforce shortages caused by two separate Omicron surges,” the first hitting its U.S. manufacturing facility in late 2021 and the second, a Canadian supplier in early 2022.

“We have been operating our manufacturing facilities around the clock to build back inventory and anticipate returning to normal levels in the coming weeks,” the spokesperson said. 

Kimberly-Clark, another major tampon manufacturer, did not respond to Fortune‘s request for comment.

At the same time that tampon brands have become more difficult to find in stores, rising inflation is driving up the prices of consumers’ now-limited menstrual product options. 

Year-over-year price increases overall were 8.6% in May, according to the latest CPI report. Compared to the beginning of this year, a box of tampons last month cost 9.8% more, and on average and a package of pads cost 8.3% more, from the start of this year through May 28, according to NielsenIQ data, Bloomberg reported. 

Citing supply costs, Procter & Gamble raised prices on its feminine care products like Always and Tampax tampons beginning in April. That’s on top of a previous increase for those products in September. 

A longtime shortage in plain sight 

For organizations that supply menstrual health products to those in need, the shortage has loomed large as early as 2020.

Kate Barker Swindell, a service manager at PERIOD, a group that once distributed 1 million free tampons in a single year, said that corporate donations started to wane in 2020, and the organization had to stop taking requests for period products several times, the latest of which was this May.

“We just don’t have inventory, so we closed down our product request form. We now have a waitlist of about 550 organizations needing products,” Swindell said. 

Freebeck said Simply The Basics receives regular donations from tampon makers. A couple of months ago, though, manufacturers started warning her of month-long delays for shipments. Simply The Basics has gone into its emergency surplus to keep distributing supplies to tens of thousands of homeless and low-income recipients, as well as nonprofit partners.

“When we commit to supplying them with so much, and we’re not able to, it really has a big impact on them,” she said. 

Freebeck worries a long-term shortage will lead to a public health crisis since not having the proper tools to manage one’s period can impact other areas of life. Nearly 1 in 5 American girls reported missed school because they didn’t have access to period products, according to a 2018 survey from Always, a major tampon brand. 

“If people don’t have access to these, they are not able to maintain employment. They’re not able to continue going to school, and they start doing tactics that are not healthy,” she said. “What we’re trying to prevent is a health crisis for people that don’t have other options.”

The executive director of Helping Women Period, Lysne Tait, too warned of an incoming hoarding problem. When people try to ration tampons, they can inadvertently cause themselves life-threatening toxic shock syndrome.

“They’ll wear them for longer than medically suggested, which then creates other medical issues like infections.” 

Tait’s nonprofit received 2,000 individual tampons through in-kind donations this May, a third less than the 3,000 donated the same month last year. The organization, which supplies menstrual products at no cost to low-income and homeless individuals, has also seen prices for the tampons it orders in bulk from a local janitorial supply company rise more than 30% since January. Last year at this time, Tait said a case of 800 pads cost $50; now the price is $75. 

“It becomes a drain on the whole society if every menstruator can’t get the product that they need, that’s best for their body,” she said.