Out-of-stock rates for baby formula started climbing last July but saw a sharp increase last November, according to Datasembly, a retail data company. Last month, 31% of formula products made by different brands were out of stock nationwide, an increase of 11 percentage points since November. And in a few major metro areas — Minneapolis, Des Moines and San Antonio — more than half of baby-formula products were out of stock.

“Inflation, supply-chain shortages, and product recalls have brought an unprecedented amount of volatility for baby formula,” Datasembly founder and CEO Ben Reich said in a statement. “We expect to continue to see the baby-formula category being dramatically affected by these conditions.”

Abbott asked consumers to return products due to contamination concerns at a Sturgis, Mich. plant that it said could cause a rare, but high-risk, infection. “If your infant is experiencing symptoms related to Cronobacter or Salmonella  infection, such as poor feeding, irritability, temperature changes, jaundice, grunting breaths, abnormal movements, lethargy, rash, or blood in the urine or stool; contact your health care provider to report their symptoms and receive immediate care,” the company said in its recall announcement.

On Wednesday, Abbott said it can restart production of its baby formulas at the plant in Michigan within two weeks if U.S. regulators allow it to do so. Once production has resumed, the company said it will take six to eight weeks to get the products back on store shelves. It also said that there is “no evidence to link our formulas to these infant illnesses,” and the genetic sequencing of samples from two ill infants did not match each other or the Cronobacter strains detected in the Michigan facility.

To manage inventory, drugstore chains CVS
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and Walgreens
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issued restrictions on purchases — limiting shoppers to three products at a time, and said they were working with vendors and suppliers to secure more supply.

Buy Buy Baby, Walmart
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and Target
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did not respond to MarketWatch’s request for comment.

A spokeswoman for Abbott told MarketWatch: “We are doing everything we can to address the infant formula supply shortage. Across the U.S., we’re prioritizing production of infant formula products to help replenish the supply in the market and are also air shipping in product from our FDA-registered facility in Cootehill, Ireland, on a daily basis.  All of this powder product is being restocked on retail shelves on a regular basis.”

Baby formula, or infant formula, has a shelf life of up to one year if the product is unopened. However, once opened, the product should be used within one month, according to U.S. Centers for Disease Control and Prevention guidelines, and within 24 hours if it’s been mixed with water. Used in place of or in combination with breastfeeding, formula is designed to meet babies’ nutritional needs.

Should you make your own baby formula?

In the face of the shortage, Google
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searches for alternatives to baby formula or DIY recipes surged this week. But pediatricians and professional trade groups — including the American Academy of Pediatricians — strongly advised against making your own baby formula at home.

“Although recipes for homemade formulas circulating on the internet may seem healthy or less expensive, they are not safe and do not meet your baby’s nutritional needs,” Steven Abrams, a board-certified pediatrician and a professor of pediatrics at the University of Texas at Austin, wrote for a Healthy Children column.

The U.S. Food and Drug Administration issued a warning last year that some babies had been hospitalized suffering from hypocalcemia (or low calcium) because of homemade recipes. “Homemade infant formula recipes have not been evaluated by the FDA and may lack nutrients vital to an infant’s growth,” it said.

Aside from insufficient nutrients, homemade formula also carries the risk of cross-contamination, Abrams warned.

Buying baby formula online from overseas is also not advised, as imported formula is not reviewed by the FDA and consumers cannot be sure that proper shipping and storage policies were adhered to. Mixing more water with formula to conserve powder is also a no-no — as it will likely result in a nutritional imbalance.

Babies under 12 months old have specific needs for nutrients. “The first year of life is a key time for your baby’s brain and body to grow,” Abrams wrote, adding that even missing those nutrients for a few days could have long-term effects on an infant’s development.

Experts say that parents should always turn to their own pediatrician for help before making new decisions about feeding their baby. For most babies without dietary restrictions, Abrams said that switching formula brands should be fine.

The Infant Nutrition Council of America has the following advice for parents who urgently need baby formula. “In emergency situations, local food pantries, churches, shelters and hospital emergency rooms may provide small amounts of infant formula that will be supplied based on need,” it said. “Contact Feeding America or dial 2-1-1 to be connected to a community resource specialist who can help you find local resources. If you have questions or concerns about feeding your infant, please contact your baby’s doctor.”