In the fall of 1958, Apgar took a sabbatical leave from her teaching and research work and began work on a masters degree in public health (MPH) at the Johns Hopkins School of Public Health. Her main goal was to become more proficient with health statistics, because so much of her work with the scoring studies involved statistics. In her evaluation of thousands of newborns, however, she had also encountered a wide range of congenital defects, and she had become increasingly interested in the connections between pregnancy conditions and such problems. She had done a small study which found correlations between hydramnios (excessive volume of amniotic fluid) and a characteristic group of birth defects. In her MPH courses, she learned more about the incidence of such problems and their status as a public health problem. Apgar was approached by the National Foundation-March of Dimes in the spring of 1959, and offered the position of chief of its new Division of Congenital Malformations. Intrigued by the idea of a career shift, she accepted, and started the new job immediately after receiving her MPH.
The National Foundation for Infantile Paralysis-March of Dimes (NF) had been founded in 1938 to help victims of poliomyelitis (also known as infantile paralysis because so many victims were children) and to fund research to eradicate the disease. Seventeen years later, Dr. Jonas Salk's research, sponsored by the NF, produced an effective polio vaccine. By 1955, a nationwide trial of the vaccine on millions of children had proved a success and polio incidence declined rapidly. While the NF continued to support polio vaccine research (it sponsored Albert Sabin's work on an oral vaccine, for example), in 1958 the organization initiated a program focused on birth defects. Like the campaign against polio, the new one included research into the causes and prevention, public and professional education about the conditions, and care for children affected by them. At the time, some 250,000 American children each year were born with birth defects, and the post-war baby boom promised that the numbers would grow. Though little was definitively known about what caused abnormalities in humans, research done since the 1920s in various fields had begun to produce many encouraging leads. The connection between infectious diseases and birth defects was being clarified, especially in the case of rubella ("German measles"). Much research had been done on teratogenesis (the causation of defects) in insects and animals by the late 1950s, and evidence was accumulating about the possible effects of radiation, chemicals such as pesticides and preservatives, and drugs and alcohol, especially on the developing fetus. Such evidence could not be applied directly to humans, but was suggestive. Meanwhile, the rapid advance of molecular biology after the 1953 discovery of DNA's structure promised to solve the mysteries of genetic coding for inherited diseases.
At the time of Apgar's NF appointment, evidence was also accumulating about the teratogenic effects of thalidomide, a tranquilizer frequently given to pregnant women in Europe. Thalidomide, soon identified as the cause of phocomelia (absent or severely shortened limbs) and other birth defects in thousands of children, brought birth defects to center of public attention. Americans were riveted by the story of the drug's effects, partly because, though used in Europe for several years, it had not yet been approved for general sale in the United States: an examiner at the Food and Drug Administration refused to approve the manufacturer's new drug application. It had been approved for investigational use, however, and there were some American cases of thalidomide damage, though far fewer than in Europe. (Publicized by a Washington Post story in 1962, this dramatic near-miss provided the impetus for passage of the 1962 Kefauver-Harris Amendments to the Food, Drug, and Cosmetic Act.) With birth defects in the headlines, Apgar and the NF had a ready audience; at the public level, there were many misunderstandings about all aspects of the reproductive process, including congenital problems. And families often coped with their affected children quietly and alone. Part of the National Foundation's goal was to resolve the misunderstandings, remove the stigma, and provide sound scientific information and hope for such families.
Apgar was highly qualified for the job; she had over twenty years of experience with patient care, and ten years of experience in neonatal research. She was a talented teacher of medical students, physicians, and patients alike. Above all, she was a "people doctor"--empathic and possessed with an ability to connect immediately with anyone. As director of the Division of Congenital Malformations she was responsible for reviewing grant applications for studies in this area, raising public and professional awareness of birth defects and the research in progress, and encouraging support for the National Foundation's research efforts. She traveled thousands of miles each year between 1960 and 1974, talking to members of NF local chapters and parent-teacher groups, speaking at professional conferences, giving interviews, appearing on television talk shows, and participating in NF fundraising events. Her efforts helped to double the annual income of the foundation during her tenure there. Apgar also contributed a much-needed resource book about birth defects, Is My Baby All Right?, to the education campaign in 1972. Written with medical journalist Joan Beck, the book provided an overview of conception, gestation, birth, and "what can go wrong and why," then discussed twenty-five of the most common congenital abnormalities, using the stories of real families as illustrations. It included information on the state of research into the various problems, and discussed the available options for prenatal screening and post-natal care.
Apgar served as Director of Basic Medical Research (1967-1968) and Vice-President for Medical Affairs (1971-1974) at the National Foundation, and also continued to teach medical students at Cornell University School of Medicine, where she was a lecturer (1965-1971), then clinical professor (1971-1974) in pediatrics, specializing in teratology, the study of birth defects. She was the first to hold a faculty position in this specialty. Apgar, a lifelong student, expanded her own knowledge of medical genetics during these years, and in 1973 was appointed lecturer in medical genetics at the Johns Hopkins School of Public Health.
By 1973, a progressive liver disease was taking its toll on Apgar, though she continued to maintain as full a schedule as possible. She died on August 7, 1974, at Columbia-Presbyterian Medical Center, where she had trained and then worked for over twenty years. Her legacy included the Apgar scoring method, now used in all hospitals worldwide, and her substantial contributions to the fields of neonatology and teratology. Equally important, in the eyes of those who knew her, was the example she set as physician, teacher, and friend. Her close friend and collaborator L. Stanley James captured this in his eulogy:
"She was one of the most remarkable people I have every known. With her, life was exciting; her youthful enthusiasm and energy were boundless. She was warm and compassionate, and at the same time had a great sense of humor, sometimes earthy. Integrity was her hallmark: she was utterly sincere and honest and could not tolerate any form of deception. Her approach was forthright, direct, realistic, and practical. She was loyal and generous, always dependable, and ready to help those in crisis. And despite her many talents, she had great humility. All these qualities, and many more, together with her magnetism and charm, contributed to her greatness..."