Contraceptive implants are registered in over 60 countries and have been used by millions of women for three decades. This article reviews findings from observational studies on the safety of contraceptive implants and examines the risk of specific health outcomes. Fifty-five articles were reviewed, and the body of evidence for each health outcome was summarized. Available evidence suggests that contraceptive implants are safe and, overall, implant users do not experience adverse events at rates higher than women not using implants. With respect to specific outcomes, the evidence suggests no increased risks of pelvic inflammatory disease, decreased bone mineral density, anemia, thrombocytopenia, or death with implant use. The evidence was too limited to draw meaningful conclusions for neoplastic disease, cardiovascular events, and HIV/AIDS. Nonsignificantly elevated associations were reported for diabetes, serious mental disorders, and rheumatoid arthritis. Conditions for which risks were marginally, yet significantly, elevated were hypertension and gall bladder disease.