The majority of referrals for fetal arrhythmias represent benign atrial premature beats. However, a small number of fetuses might have life-threatening conditions associated with bradycardia or tachycardia. Fetal echocardiography is essential to establish the diagnosis. Transplacental treatment is most often used to prevent heart failure. There is no clinical trial evidence as to the drug of first choice. Prognosis is determined by the type of arrhythmia, the association with structural cardiac anomaly and the co-existence of intrauterine cardiac failure. Treatment of fetal dysrhythmias should be executed in experienced maternal-fetal medicine centers.