Today, as World Prematurity Day is observed on Nov. 17, things are better than ever for premature babies. In fact, as the medical director of the March of Dimes explained to TIME in a cover story last year about the cutting-edge science used to save preemies, “Every decade since the 1960s, the age of viability [at which a baby can survive outside the womb] has been reduced by a week.”
Before 1960, however, things were different. Up until the early 20th century, the concept of a premature baby didn’t even really exist, as there was little that doctors could do for them. Their death was assumed, so special medical research would have seemed like a low priority. Those who did survive were often dismissed as weaklings.
Then came Arvo Ylppö. The Finnish doctor—who had been born prematurely himself, according to the U.S. National Library of Medicine—made premature babies his specialty.
“As early as 1913 came a study of jaundice from blood destruction, which sometimes afflicts the newborn. By 1917 Ylppö had passed a tube into his own stomach and pumped oxygen in to prove that the life-essential gas could be given by this route (he was the first to apply this technique to “preemies”),” TIME noted when he turned 70 in 1957. “Then came detailed studies of the physiology of preemies (showing just what development handicaps they suffered), and other vital topics, such as the effects of a mother’s illnesses on her unborn child, and what substances, from hormones to antibodies, pass through the placenta from mother to child.”
“It is often stated that Arvo Ylppö invented the premature baby,” Clement Smith, a Harvard researcher in newborn respiration, was quoted saying. “I doubt this, but it certainly was fortunate for premature infants that Arvo Ylppö was invented.”
Read TIME’s 2014 cover story about how far preemie care has come: Saving Preemies
What the Battle to Save Preemies Looked Like 75 Years Ago