Douglas, Mass. — A growing number of states are passing laws to protect patients from surprise medical bills. Fifty-seven percent of Americans have been hit with a bill they thought would be covered by insurance and 20 percent of those bills were from doctors outside their insurance networks.

It was pure bliss for Adam and Laura Parkinson when their son, Nathan, arrived 13 months ago. Then within days came a second delivery. They received a surprise medical bill for $3,700.

"For a doctor that we've seen for five minutes to give us a bill like this. It was crazy," said Adam Parkinson.

They'd done their homework, choosing an in-network hospital and obstetrician to avoid any surprises. But the anesthesiologist, who administered an epidural for Laura was out-of-network. After an appeal, insurance paid a portion. But the Parkinsons were on the hook for nearly $1,500.

"You go to a hospital expecting it to be in network. You don't have to ask a question of every single person who walks in the door, hold on are you in-network," Adam said.

A survey of in-network hospital admissions in 37 states found one in seven patients received a surprise bill. Anesthesiology accounted for the largest share of out-of-network claims.

Massachusetts Attorney General Maura Healey said new federal laws are needed.

"We do have a law here in Massachusetts. It's a consumer law that says you can't hide the ball from consumers. You need to be transparent, you need to make disclosures," Healey said.

The Parkinsons called Healey's office and eight months later, the doctor's group agreed to drop the balance.

"It's OK to question the bills that come in," Laura Parkinson said.

A simple question before costs nothing. A surprise answer later may be very expensive.