This paper reports on our interdisciplinary research on stress management for pregnant women. We developed a mobile app – PositivelyPregnant – for supporting the mental wellbeing of pregnant women in New Zealand. The app aims to support women in using the time during pregnancy to build resilience and plan a healthy future for the whole family. We report the results from a study using PositivelyPregnant, carried out at 24 weeks gestation with 88 women. We particularly explored the use of prompts for continued engagement.