Background: Gestational diabetes mellitus (GDM) screening is commonly undertaken using the oral glucose tolerance test (OGTT), yet some women decline testing and many describe significant burden after diagnosis. Theoretical Domains Framework (TDF) has recognised utility in supporting better understanding of contextual and/or system factors that influence behaviours, perceptions and experiences. We used TDF to examine cognitive, emotional, social and structural influences shaping (1) decisions to decline OGTT and (2) experiences of living with a GDM diagnosis.
Methods: The TDF was applied as an interpretive lens to integrate qualitative accounts from two separate national study phases: i) open-ended survey responses (n=386) and ii) interview transcripts (n=35). Inductive thematic analysis was conducted, followed by deductive mapping of the findings to the 14 TDF domains.
Results: Women declined OGTT based on informed, deliberate choices rooted in autonomy and psychological safety, not disengagement or non-compliance. GDM diagnoses caused emotional strain, identity disruption, and reduced agency, often worsened by fragmented models, risk-focused care and inflexible systems. Both groups’ behaviours were shaped by capability, opportunity, motivation, environmental factors, and clinician interactions. Continuity of care facilitated more positive experiences of clinician-woman interactions resulting in shared negotiation of plans of care, indicating the need for personalised care models that support informed choices and consider broader social influences.
Conclusion: Interpreted through the TDF, declining OGTT in this study population is best understood as a reasoned/ considered, values-based health behaviour shaped by interacting cognitive, emotional, social, and structural determinants, rather than as non-compliance or disengagement from care. Findings highlight the need for better system-level processes to support informed decision-making, and proportionate risk communication. Enablers include continuity of care, and flexible, evidence-informed screening and monitoring approaches that actively support psychological wellbeing and promote health equity.