Gestational cancer is defined as any type of cancer diagnosed during pregnancy or within 12 months of delivery. To date, existing studies on the psychological aspects of this type of cancer have not been evaluated for methodological quality. The aim of this systematic review was to identify the psychological aspects of gestational cancer. Five journal databases were searched to identify peer-reviewed articles reporting upon the psychological aspects of women with gestational cancer. Studies published from journal inception to December 2019 were included, and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed. The Mixed-Method Appraisal Bias Tool was used, to assess the methodological quality of the studies. A narrative description was developed for the psychological outcomes reported in quantitative studies. Qualitative data was synthesized using thematic analysis. Five papers were eligible for inclusion (two qualitative and three quantitative studies). Factors that contributed to women's psychological distress during gestational cancer included disease characteristics, sociodemographic factors, the baby's health, pregnancy-related factors and cognitive emotion regulation. Four main themes emerged from the qualitative studies; concerns about the baby's health, lost opportunities, "not fitting in," and healthcare decision-making. These findings suggest that (a) women with gestational cancer experience psychological distress that is associated with concerns about their babies' health, and (b) their healthcare experiences are affected by communication within multidisciplinary care teams.