Photo/IllutrationShunta Yamada in Sapporo on Sept. 11, five days after he was born on the morning that a powerful earthquake struck Hokkaido (Miki Aoki )

SAPPORO—Her labor pains were intensifying, but Aki Yamada said she only started to feel really scared when the hospital room jolted vertically at 3:08 a.m. on Sept. 6.

“What’s going on?” Yamada, 39, said she thought at the time.

The most powerful earthquake recorded in Hokkaido’s history had struck just as Yamada was being prepped for delivery of her baby.

Yamada herself grew up in Sapporo but she now lives in Tokyo. She was staying at her parents’ home in the Hokkaido capital so that they could lend a hand in the final weeks of her pregnancy.

Just after 3 a.m., Yamada was in a wheelchair being pushed by a young midwife at Sapporo Maternity Women’s Hospital.

The moment they arrived at the delivery room, the magnitude-6.7 earthquake struck southeast of the city with an intensity that reached a maximum 7 on the Japanese seismic scale. The intensity in Sapporo was upper 5.

The midwife bent over Yamada to protect her and her unborn child from possible falling debris.

“It’s OK, it’s OK,” the midwife said.

Power was immediately cut to the hospital, and an emergency backup generator was turned on.

The corridor and ordinary patients’ wards were dimly lit, but the delivery room returned to its normal brightness.

“The contractions were painful, the building was shaking, and I was so worried about my baby,” Yamada said.

As aftershocks continued to rattle the area, Yamada concentrated on her labor. Hospital staff cheered her on while her husband supported her body.

At 5:43 a.m., Yamada’s baby boy, her first child, emerged with a loud cry.

The parents named him Shunta.

“He overcame the earthquake and the typhoon that hit just before he was born,” Yamada said. “I would like him to be a big-hearted person.”

On Sept. 11, Yamada and Shunta left the hospital.