To assess whether maternal breast implants are related to adverse health outcomes in offspring, the authors conducted a retrospective cohort study of esophageal disorders, rheumatic disease, and congenital malformations among 2,854 children born to women with breast implants and among 5,805 children born to a comparison group of women who underwent breast reduction or other plastic surgery. Rates were calculated using both hospitalization and outpatient data. Significantly higher rates of esophageal disorders were observed (O) than were expected (E) for children born before (O/E, 2.0; 95% CI, 1.3-2.8) but not after (O/E, 1.3; 95% CI, 0.5-2.9) maternal breast implant surgery. Risk of rheumatic disease was similar among children born before (O/E, 1.4; 95% CI, 0.7-2.6) and after (O/E, 1.4; 95% CI, 0.2-5.0) maternal breast implant surgery. A marginally significant excess of congenital malformations of the digestive organs was observed among children born after maternal implant surgery (O/E, 1.8; 95% CI, 1.0-3.1), with a similar finding among children born to women in the comparison group (O/E, 1.9; 95% CI, 1.4-2.4). The risk of malformations overall was not statistically significantly higher than expected among children born after maternal breast implant surgery. The elevated risks of adverse health outcomes appear unrelated to breast implants per se, because similar findings were observed among children born both before and after the mother's implant surgery, as well as among children born to mothers in the comparison cohort.