Looking around for an appropriate animal model on which to test his hypothesis, he naturally turned his attention to sheep. Even today, there are 13 sheep for every man, woman, and child in New Zealand. In a makeshift laboratory that he set up in an abandoned shed, Dr. Liggins began infusing sheep with corticosteroids to see sellectchem what effect it had on the timing of labor. And that was when a chance observation changed the course of obstetric history. One morning, Dr. Liggins discovered that a sheep he had infused with corticosteroids had delivered overnight. The lamb was so premature that it should not have survived, and yet there it was, alive and breathing. In collaboration with his pediatric colleague, Dr. Ross Howie (previous page, left), Dr.
Liggins went on to demonstrate that antenatal corticosteroids administered to pregnant women threatening to deliver prematurely cross the placenta and induce a wave of cellular differentiation that results in a 50% reduction in respiratory complications (the final organ system required for extrauterine life) and a comparable decrease in perinatal mortality. This discovery likely represents the single greatest collaboration between an obstetrician and pediatrician in medical history. There is no doubt that the intervention they described has saved the lives of hundreds of thousands of tiny premature infants and saved families and society from the personal and financial burden of a lifetime of caring for a handicapped child.
Although numerous studies have confirmed these observations, none have yet managed to improve on the timing and dosage regimens described by Liggins and Howie in their original manuscript, published in Pediatrics in 1972.1 That said, a number of outstanding issues remain.2 What is the optimal timing of antenatal steroid administration? How early in gestation can it be given? What is the best formulation? Should a repeat or ��rescue�� course be administered if the first course is given early in gestation? Is there any risk to the mother or fetus? What is the effect of antenatal steroids on long-term neurodevelopment in the offspring? Do they increase or decrease the risk of cerebral palsy? And��perhaps most importantly��exactly how do steroids work on a molecular level to promote cellular differentiation in the developing fetus? Sadly, Dr. Liggins is no longer around to help us answer these questions.
We are going to have to solve them on our own. So what exactly is Dr. Liggins��s legacy? There is no doubt that his incidental finding of the beneficial effects of antenatal corticosteroids is one of the most important discoveries in obstetrics, and an entire generation of premature infants and their families owe him a debt of gratitude. But there are additional lessons Entinostat that can be learned even by those of us who have not been touched personally by his discoveries: Medical advances are universal. Dr.