Birth defects are common, costly, and critical conditions that affect 1 in every 33 babies born in the United States each year.
Most birth defects are thought to be caused by a complex mix of factors, including a person’s genes, behaviors, and things in the environment.
Exposure to hazards in the physical environment—secondhand smoke, lead, mercury, air pollution, pesticides, and other toxins—may increase the likelihood of poor reproductive health outcomes.