Ellen Tilden, a certified nurse midwife practicing in a hospital who was an author of the study, said she hoped the results “will be used to think about decreasing risk in all birth settings.”

Erin Dietrich would welcome that. Ms. Dietrich, 35, had her first child in 2011 at a midwife’s house in isolated Otis, Ore. She said she loved the “hippy kind of alternative birth thing,” but suffered a “pretty bad tear” that the midwife did not treat. “I was in a lot of pain for a long time until I finally saw a regular doctor.”

For her second child, she chose a big Portland hospital with a bathtub-equipped birthing suite and a nurse midwife. But when she arrived, she had to wait for a room and received notably less individual attention, she said.

Still, when she had a tear, “they stitched me right up and I healed so quickly and I felt great,” Ms. Dietrich said. “I was shocked: This is what actual care can do.”

Anna Hope-Melnick, 32, is a labor and delivery nurse at a hospital in Hillsboro, Ore., but wanted a home birth in 2012 because in the hospital “it’s not just about the one-on-one needs of the family; it’s about the whole overarching system.”

But after her water broke and she labored for 40 hours at home and developed a fever, her midwife told her to go to a Portland hospital. That “was absolutely the right choice,” she said and she gladly accepted the drug Pitocin, to jump-start labor, and an epidural to help her relax. Even so, she said hospital staff members overreacted to some symptoms.

“They kind of assumed that we were idiots, and why would you stay home for 40 hours?” she said. When her daughter was born, “she was showing no signs of distress, but they went full-court press with breathing tubes, suctioning” and neonatal intensive care, she said.