Introduction The fourth trimester or postpartum period is a concept that places the woman (newborn and couple) at the centre of care, within the family. In this study, an instrument was developed to enable the puerperal woman/couple to plan and organise the postpartum period, in order to facilitate adaptation during this period. The theoretical framework of Laurie Gottlieb's Strengths-Based Nursing Care guided this process. Objective This study begins with the research question: What difficulties does the puerperal woman experience in the postpartum period? Its objectives are: to identify the triad's bio-psycho-social needs in the first 12 weeks postpartum, the puerperal woman's/couple's strategies for overcoming perceived difficulties and the items to be included in the postpartum plan, from the maternal perspective. Methods A descriptive exploratory study with a mixed-methods approach, with a questionnaire administered to mothers aged between 18 and 39, obtaining 141 responses with eligibility criteria between April 14 and May 5, 2023. The data collection tool was shared through groups of mothers on social networks (Facebook, Instagram, WhatsApp). Content analysis was carried out according to Bardin and semantic categorization was used to process the qualitative data and statistical analysis of the quantitative data. Results The study revealed the difficulties, the needs of the triad in the first 12 weeks, the strategies or strengths to overcome the difficulties and the suggested items for the postpartum plan. Conclusion It can be concluded that the postpartum plan is an innovative concept, since pregnant women/couples focus on drawing up the birth plan, unaware of or not valuing the postpartum plan. However, most of the participants considered planning to be one of the strengths or strategies for a positive experience of the fourth trimester.