Women with previous gestational diabetesmellitus(GDM) are more than eight times more likely to develop type 2 diabetes (T2DM) compared to women without GDM. Annual follow-up T2DM-screening is recommended, but participation rates decrease rapidly after the first year. In the North Denmark Region, an electronic reminder has been tested with the aim of improving follow-up care for women with prior GDM. The aim of this study was to explore women's perspectives on receiving an electronic reminder, and the role of reminders in both women's decision-making and informed choice regarding participation in follow-up screening. A qualitative process evaluation informed by a critical realistic perspective. Data consisted of 20 semi-structured interviews with women previously diagnosed with GDM who had received the reminder. Interviews were analyzed using reflexive thematic analysis. The reminder affected women's decision-making and informed choices through a range of mechanisms. Its personalized design prompted feelings of co-responsibility and care from the healthcare system, supported continuity in women's care pathways, and helped women bridge the gap between healthcare sectors. Women's perception of diabetes risk and the importance of follow-up influenced their decision-making. Participation in follow-up screening was influenced by several contextual factors, as women's everyday life impeded their prioritizing follow-up screening. Women who experienced being met by their general practitioner (GP) with acknowledgement rather than stigmatization and received supportive information tailored to their life situation were more motivated to participate in future follow-up screenings. The reminder indicated both concern and co-responsibility for women's follow-up care after GDM and was well received by the women. It supported participation in follow-up screening through an emphasis on shared decision-making and informed choice. Women's interaction with their GP played a significant role.