World's smallest baby boy — born at just 24 weeks — leaves hospital after spending 5 months in ICU

The world's tiniest baby boy was born in Tokyo in August at a mere 24 weeks' gestation.

The little boy weighed just 9.45 ounces at birth. He spent five months in the intensive care unit before doctors discharged him at a robust seven pounds.

The baby went home with his family on Feb. 20.

What are the details?

Physicians delivered the unnamed child via emergency C-section when his mother was just 24 weeks along in her pregnancy because the child stopped gaining weight and doctors feared for his life.

The child was so small he could fit in the palms of an adult's hands, according to CNN.

Dr. Takeshi Arimitsu, one of the child's doctors, told the outlet that the baby needed a ventilator for breathing and an umbilical catheter for nutritional support. While in the intensive care unit, the boy continuously gained weight.

"I am grateful that he has grown this big because, honestly, I wasn't sure he could survive," the child's mom told Reuters.

According to the University of Iowa's Tiniest Babies registry, a German baby born at 9.66 ounces at birth previously held the record for the world's smallest surviving baby boy.

A baby girl — also born in Germany — survived after weighing in at just 8.8 ounces at birth.