Background: Maternal and child health outcomes are positively influenced with early intervention, and digital health (DH) tools provide the potential for a low-cost and scalable solution such as informational platforms or digital tracking tools. Despite the wide availability of DH tools out there for women pre-to post-pregnancy, user engagement remains low.Objective: This study aims to explore the factors that shapes women's DH adoption and sustained usage across the maternal journey from pre-conception to post-birth, to improve user engagement with DH tools.Methods: 1-hour semi-structured qualitative interviews were conducted with 44 women from pre-to post-pregnancy (age range: 21-40 years) about their experiences with DH. This study is part of a larger study on women's maternal experiences with healthcare and DH, and focuses on the factors that affected women's DH adoption and sustained usage. Interviews were audio recorded, transcribed verbatim and analysed using inductive thematic analysis.Results: Five main themes and ten subthemes were identified that affected women's adoption and sustained usage of DH tools. These included themes on their pre-existing attitudes to DH, perceived ease of use, perceived usefulness, perceived credibility and perceived value of the tool.Conclusions: Themes that emerged were fully or partially mapped according to the Unified Theory of Acceptance and Use of Technology (UTAUT) 2 model. The applicability of the model and need to consider specific cultural nuances in the Asian context (such as the importance of trust and social influence) are discussed. The interaction of the five themes with DH adoption and sustained usage are explored with different themes being relevant at various points of the DH adoption journey. The insights gained serve to inform future DH design and implementation on tools for women to optimise their DH engagement and the benefits they derive from it. Clinical Trial: NCT05099900