Teratology Transformed: Uncertainty, Knowledge, and Conflict Over Environmental Etiologies of Birth Defects in Midcentury America

This dissertation traces the academic institutionalization and evolving concerns of teratologists, who studied environmental causes of birth defects in midcentury America. The Teratology Society officially formed in 1960, with funds and organizational support from philanthropies such as the National Foundation (Later known as The March of Dimes Birth Defects Foundation). Teratologists, including Virginia Apgar, the well-known obstetric anesthesiologist and inventor of the Apgar Score, were soon embroiled in public concerns about pharmaceutically mediated birth defects. Teratologists acted as consultants to industry and government on pre-market reproductive toxicology testing for pharmaceuticals. However, animal tests seemed unable to clearly predict results in humans and required careful interpretation of dosage and animal species and strain responses. By the late 1960s, amidst the popular environmental movement, teratologists grappled with public claims that birth defects resulted from exposure to industrial pollutants in water or air, or from food additives, pesticides, and industrial waste or effluent. In a crowded field of professionals concerned with pharmaceutical or chemical exposures during pregnancy, teratologists proved adaptive and resilient. Despite influences from the environmental movement, teratologists at times tried to contain the substances and outcomes considered relevant and called for greater vetting of chemical claims, amidst rampant journalistic and public accusations about iatrogenic or industrial harm. Both experimental teratology and epidemiology informed these debates but each faced explanatory insecurities in causal inference that left room for parental anxiety and considerable speculation about uncertain harms to susceptible fetuses. Concomitantly, environmental scientists and activist geneticists wanted to expand the definition of a teratogen to include more subtle or long-term outcomes and raising concerns about the as-yet-undetected r