During pregnancy and the early parenting period, women are especially vulnerable to intimate partner violence (IPV), with devastating impacts on women, children, and families. The aim of this systematic review was to determine the effectiveness of father-focused interventions to prevent or reduce IPV during pregnancy and early parenthood. Six databases were searched, using a combination of the concepts “fathers,” “pregnancy/early parenthood,” “IPV” and “intervention.” Articles were double screened by title and abstract, and then full-text. Methodological and reporting quality was assessed using the Quality Assessment with Diverse Studies tool. Fifteen papers were eligible for inclusion; these articles were mostly of poor-to-moderate quality. Only three of the articles reported on interventions in lower- and middle-income countries. The most common forms of IPV addressed in these interventions were physical (10), psychological (8), sexual (4), and economic/financial (3). Of 12 articles reporting on data from both intervention and control groups, only six indicated statistically significant results; among these, only three reported robust analyses showing significantly greater reduction in IPV in intervention than in control groups. All three took place in lower- or middle-income countries. Two were underpinned by theoretical frameworks, which considered transforming traditional perceived gender norms. Therefore, interventions based on principles that address transformation of gender norms show promise but the success of such underlying principles needs to be confirmed, and better-quality evidence and reporting are needed for interventions targeting fathers to prevent or reduce IPV.