BACKGROUND: Breast augmentation is the most commonly performed procedure for gender affirmation in transfeminine individuals. Although adverse events among breast augmentation in cisgender women are well described, their relative incidence in transfeminine patients is less elucidated. This study aims to compare complication rates after breast augmentation between cisgender women and transfeminine patients and to evaluate the safety and efficacy of breast augmentation in transfeminine individuals. METHODS: PubMed, the Cochrane Library, and other resources were queried for studies published up to January of 2022. A total of 1864 transfeminine patients from 14 studies were included in this project. Primary outcomes including complications (capsular contracture, hematoma or seroma, infection, implant asymmetry/malposition, hemorrhage, skin or systemic complications), patient satisfaction, and reoperation rates were pooled. A direct comparison of these rates was performed against historical rates in cisgender women. RESULTS: Within the transfeminine group, the pooled rate of capsular contracture was 3.62% (95% CI, 0.0038 to 0.0908); the hematoma/seroma rate was 0.63% (95% CI, 0.0014 to 0.0134); the infection incidence was 0.08% (95% CI, 0.0000 to 0.0054); and implant asymmetry rate was 3.89% (95% CI, 0.0149 to 0.0714). There was no statistical difference between rates of capsular contracture ( P = 0.41) and infection ( P = 0.71) between the transfeminine versus cisgender groups, whereas there were higher rates of hematoma/seroma ( P = 0.0095) and implant asymmetry/malposition ( P < 0.00001) in the transfeminine group. CONCLUSION: Breast augmentation is an important procedure for gender affirmation and, in transfeminine individuals, carries relatively higher rates of postoperative hematoma and implant malposition relative to cisgender women.