George Frederic Still studied pediatrics and childhood conditions in England during the early twentieth century. In Still’s time, pediatrics, or the branch of medicine that focuses on treating and caring for children, remained largely unexplored according to biographer Joseph deBettencourt. Still helped advance pediatrics as a field by classifying and writing about diseases and conditions that arose in children. In 1897, he discovered a unique type of arthritis in children, now referred to as Still’s disease. Still also was one of the first to correctly describe what is now known as attention deficit hyperactivity disorder, or ADHD, a disorder that can cause children to act impulsively and have trouble focusing, among other behaviors. He shared his understanding of those conditions and pediatrics as a whole in a popular textbook called Common Disorders and Diseases of Childhood. Still’s work helped establish pediatrics as a separate field of medicine and provide a foundation for pediatricians throughout the twentieth century to understand and expand on a variety of conditions developing children can face.

Michael R. Harrison worked as a pediatric surgeon in the US throughout the late-twentieth century and performed many fetal surgeries, including one of the first successful surgeries on a fetus in utero, or while it is still in its gestational carrier’s body, also called open fetal surgery. A fetus is an organism developing inside of the uterus that is anywhere from eight weeks old to birth. Harrison hypothesized that open fetal surgery could correct developmental defects that may become fatal to the fetus at birth. After years of research, Harrison and his colleagues at the University of California, San Francisco, in San Francisco, California, performed surgery on the fetus of a woman in her seventh month of pregnancy to correct the fetus’s developmental defects. The surgery was successful, as the fetus developed into a healthy child. Harrison’s work led to advancements in fetal treatment techniques, such as a method to conduct open fetal surgery that will not harm the fetus or pregnant woman, as well as the establishment of one of the first fetal treatment centers in the US.

In the late-twentieth century in the United States, Catherine DeAngelis was a pediatric physician, researcher, and editor of multiple medical journals. During her time with the Journal of the American Medical Association, DeAngelis became the journal’s first female editor. At Johns Hopkins University in Baltimore, Maryland, she studied how physician-nurse interactions affected patient care, how immunizations and adolescent pregnancy affected children, and how medications affected men and women differently. She also worked to reduce gender inequality in the practice of medicine by publishing articles that addressed the pay gap between men and women at Johns Hopkins. Throughout her career, DeAngelis advocated for equality between men and women in the medical field and supported equal treatment of women as patients and as practitioners of medicine. By doing so, she helped women become more central participants in medicine and therefore helped increase the focus on women's health in medicine.