The fact that certain vaccines are grown in cell strains derived decades ago from an aborted fetus is a concern for some. To understand such concerns, a standardized search identified internet sites discussing vaccines and abortion. Ethical concerns raised include autonomy, conscience, coherence, and immoral material complicity. Two strategies to analyse moral complicity show that vaccination is ethical: the abortions were past events separated in time, agency, and purpose from vaccine production. Rubella disease during pregnancy results in many miscarriages and malformations. Altruism, the burden of rubella disease, and protection by herd immunity argue for widespread vaccination although autonomous decisions and personal conscience should be respected.