Redefining maternal disease: A systematic review of the convergent cardiometabolic–respiratory syndrome linking obesity, heart failure with preserved ejection fraction, pulmonary hypertension and sleep-disordered breathing in pregnancy

ABSTRACT

Cardiometabolic and respiratory disorders are increasingly recognised as major contributors to severe maternal morbidity; however, they continue to be examined largely in isolation in both research and clinical practice. Across recent literature, there is a growing suggestion – not always explicitly stated – that conditions such as obesity, sleep-disordered breathing, pulmonary hypertension and heart failure with preserved ejection fraction may not operate independently, but rather intersect through overlapping physiological stress pathways unique to pregnancy. Therefore, this review aimed to explore whether these coexisting conditions might be better understood within an integrated framework rather than as discrete entities. In line with PRISMA guidance, we systematically searched major databases and registries, using predefined criteria to guide study selection and synthesis. After removing duplicates and screening the available reports, we included 33 studies. Despite differences in study design and diagnostic definitions, particularly for heart failure phenotypes, a consistent pattern has emerged: metabolic inflammation, endothelial dysfunction, intermittent hypoxia, impaired ventricular relaxation and progressive pulmonary vascular load have recurred across the literature. These processes, often described separately, seem to cluster and intensify across gestation, potentially narrowing the cardiopulmonary reserve and amplifying the haemodynamic strain. Clinically, this convergence is associated with increased rates of hypertensive complications, pre-term birth, foetal growth restriction, respiratory compromise and peri-partum instability. However, the heterogeneity of the available evidence and the absence of standardised definitions limit direct comparability and preclude causal inference. Taken together, these findings support the proposed integrative interpretation of the interaction between cardiometabolic and respiratory dysfunction during pregnancy. Further prospective and mechanistic studies are needed to clarify these relationships and determine whether earlier recognition of such patterns can improve maternal and foetal outcomes.