Background: Unexpected news in Fetal Medicine (FM) includes suspected fetal anomalies, uncertain ultrasound findings, or risks that may alter pregnancy management or outcomes. How such news is communicated can have lasting emotional and decisional consequences, particularly for women with pre-existing mental health conditions (MHCs). Objective: To explore communication practices used by FM healthcare professionals (HCPs) when delivering unexpected news to pregnant women with MHCs. Design: Qualitative co-production study Setting: Three FM services in East London, UK Population: Pregnant women with pre-existing MHC attending FM consultations, their accompanying significant others, and FM HCP. Methods: Twenty-one real-life FM consultations were audio- and/or video-recorded. Recordings were analysed collaboratively by academic researchers and public contributors with lived experience using applied conversation analysis. Main outcome measures: Observable communication practices and their interactional consequences within consultations. Results: Communication practices that supported understanding and emotional containment included clear and inclusive opening practices, explanation of ongoing activities, use of accessible language, acknowledgement of emotional cues, allowing time for processing, and involvement of significant others. Practices associated with noticeable uncertainty or distress included rushed encounters, unexplained silences or questions, technical language without clarification, vague reassurance, missed emotional cues, and exclusion of companions. Conclusions: This co-produced analysis identifies communication practices that shape how unexpected news is experienced in FM consultations. The findings can inform training and service development to support clearer, more empathetic, and more inclusive communication, particularly for women with MHCs.