This study aims to identify differences between single and repeat perpetrators of filicide by using register-based data. The study used register-based, comprehensive, nationwide data from both Austria and Finland. The current study covers 23 perpetrators, 20 single and 3 repeat perpetrators, with a total of 28 victims. All victims had a maximum age of 24 h and all perpetrators were women. Every third victim of neonaticide was a victim of a repeat case. The repeat perpetrators were older; had a higher number of children over their lifespan, some of whom lived with them; were more likely to live within established family structures; had higher levels of education and employment; had a higher proportion of personality disorders; and were more likely to identify stress factors during pregnancy. One unexpected finding was low levels of awareness about pregnancy within the perpetrator's circle remain a risk factor, especially for repeat perpetrators. Arguably, the quality of interpersonal relationships these women have may be affected by their own mental health issues and life experience and vice versa.