Roberto Caldeyro-Barcia (26 September 1921 – 2 November 1996) was a Uruguayan doctor who pioneered the field of maternal-fetal medicine, or perinatology. His research with Dr. Hermógenes Alvarez created Montevideo units, a measure of uterine performance during labor. He was a founding editor of the Journal of Perinatal Medicine, a widely published author, a lecturer, and the only Uruguayan to be nominated for a Nobel Prize. Early life Caldeyro-Barcia's father, Joaquin, was a physician. His mother, Elvira, came from a family with a medical background. While attending the English School in Montevideo, Caldeyro-Barcia was given the nickname "Bobby" by the headmistress, Ivy Thomas. His family and close friends called him "Bobby" throughout his life. Caldeyro-Barcia enjoyed sports; at the age of 15, he started to court his neighbor and horseback-riding partner, Ofelia Stajano. They became engaged in 1945, and were married in 1946. At age 17, Caldeyro-Barcia started studies under the Faculty of Medicine at the University of the Republic in Uruguay. He specialized in obstetrical physiology under the influence of outstanding researchers like Corneille Heymans (winner of the Nobel Prize for Physiology or Medicine, 1938) and Bernardo Houssay (co-winner of the Nobel Prize for Physiology or Medicine, 1947). He qualified in medicine nine years later. Early career Barcia graduated in December 1947. Upon graduating, he was appointed Assistant Professor of Physiology in the Institute of Physiology in Montevideo. At the School of Medicine of Montevideo, he was instructor of Physiology (1942–1947), Assistant Professor of Physiology (1948), Associate Professor of Physiology (1950), Head of the Department of Obstetrical Physiology (1959), and Professor and Chairman of Physiology (until 1965). Montevideo units In 1947, while still a medical student, Caldeyro-Barcia first collaborated with his Professor of Obstetrics, Hermógenes Alvarez. Together, they established a tracing system to monitor intrauterine amniotic pressure during pregnancy and labor by measuring the intensity and frequency of contractions and the uterine tone, making it possible to analyze and define uterine contractility during pregnancy and childbirth. This research—which included the first recording of human uterus activity during labor— led to the duo's creation of Montevideo units to quantify uterine activity, now a worldwide standard in perinatal care. In 1950, he recorded for the first time intramiometrial pressure in different parts of the uterus during labor, defining the pattern of normal uterine contractility having a "triple descendant gradient". Later career In 1958, Caldeyro-Barcia and Alvarez developed a method to measure