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Across Massachusetts, milk banks that collect and distribute donated breast milk for premature babies and other babies who need specialized nutrition are now fielding extra calls.

Parents with healthy but hungry babies are calling, too.

Hundreds of bottles of donated breast milk are carefully stored in the cooler at the Mother's Milk Bank Northeast in Newton.

"Most of this is going to be shipped out to hospitals, but some of it will be able to go to families," Deborah Youngblood, who works at the milk bank said.

Youngblood said in the past few days, about 30 percent more families than usual are calling, looking for breast milk.

The number of donors has also increased, but Youngblood says sooner or later, the bank might have to turn some families away.

"Right now, what we've been able to say to parents is we'd be happy to supply you, but we have a limited amount," Youngblood said. "So, we could supply you with about 10 bottles of milk."

It's a limited solution and an expensive one.

Each eight ounce bottle of milk, enough for one feeding, costs more than $14.

Still, doctors say some families who would otherwise use formula, are switching.

"I don't think we have any handle on the scope of switching at this point," Dr. Rachel Rosen with Boston Children's Hospital said. "Even in our own hospital, it's just really hard to keep track because families are getting whatever they can get."

The formula shortage may encourage more new mothers to try breast feeding on their own, but doctors say for some, that's just not possible.

"Especially in our babies who have allergies, mothers have to cut out several things in their diet and their milk supply goes down," Dr. Navneet Hundal, a Massachusetts General Hospital pediatrician said. "So it's not an option."

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