Origin of congenital heart disease: reflections on Maude Abbott's work.

In honour of Dr Harold Segall's 90th birthday an historical review was made of concepts on the etiology of congenital heart disease. The work of Maude Abbott, highlighted in alignment with early results of an ongoing population based study, illustrates her remarkable perception of a kaleidoscope of risk factors which are now gaining acceptance. Abbott's letters to L. Emmett Holt express her belief that prenatal infections cause cardiac maldevelopment, but she also raises relevant questions on the potential role of inheritance. The Baltimore-Washington Infant Study (1981-86) reveals a predominance of genetic factors, evidence of intrauterine infection and of a teratogenic effect of maternal diabetes. Among environmental agents, alcohol and recreational drug intake appear to affect cardiac looping. Harold Segall's historical interests and continued professional activities demonstrate the validity of his scholastic motto: "It is good to know."