BACKGROUND: Human-centered design is a methodology that applies an iterative participatory process that engages the end-user for whom an innovation or intervention is designed for from start to end. There is general evidence to support the use of human-centered design for development of tools to affect health behavior, but specifically for family planning provision. This study is part two of a three-phase study that uses a user-centered design methodology which uses the findings from Phase I to design, develop, and test a digital health solution to support follow-up after an induced surgical abortion. OBJECTIVE: The objectives for this study were to: (1) develop a Web-based intervention based on preferences and experiences of women who underwent an abortion as measured in the formative phase of the Feasibility and Acceptability of a Mobile Technology Intervention to Support Postabortion Care Study; (2) conduct usability testing of the intervention to determine user-friendliness and appropriateness of the intervention; and (3) finalize a beta version of the Web-based intervention for pilot testing. METHODS: The study design was based on the "development-evaluation-implementation" process from the Medical Research Council Framework for Complex Medical Interventions. This study is in Phase II of III and is based on user-centered design methodology. Phase I findings demonstrated that women engage with technology to assist in clinical care and they preferred a comprehensive website with email or text notifications to support follow-up care. In Phase II we collaborated with family planning experts and key stakeholders to synthesize evidence from Phase I. With them and a development partner we built a prototype. Usability testing was completed with 9 participants using a validated System Usability Scale. This was then used to refine the intervention for Phase III pilot study. This study was approved by the local Ethics board. RESULTS: We developed a comprehensive Web-based tool called myPostCare.ca, which includes: Post-Procedure Care, Emotional Well-Being Tool, Contraception Explorer, Sexual Health, Book an Appointment, and Other Resources. Additionally, over the course of a month after the procedure, automatic email notifications were sent to women as a form of virtual follow-up support, directing them to myPostCare.ca resources. The Web-based tool was refined based on usability testing results. CONCLUSIONS: This study demonstrated that user-centered design is a useful methodology to build programs and interventions that are women-centered, specifically for abortion care.