Leukocyte Variations in Gestational Hypertension: An Immunohematological Review

Abstract

Gestational hypertension (GH) is a hypertensive condition of pregnancy characterised by the emergence of hypertension after 20 weeks of gestation, in the absence of proteinuria or systemic organ involvement. Although preeclampsia has been thoroughly studied, the modifications in leukocytes associated with gestational hypertension have garnered relatively little attention, despite common immunological mechanisms. Physiological pregnancy is characterised by leukocytosis, mostly induced by neutrophilia, alongside relative lymphopenia, which indicates an innate–adaptive immunological transition. In GH, data suggests further enhancement of these alterations, encompassing raised total white blood cell (WBC) counts, an increased neutrophil-to-lymphocyte ratio (NLR), monocyte activation, and heightened systemic inflammatory indices. These results correspond with a condition of increased maternal systemic inflammation, endothelial dysfunction, and placental maladaptation. This review integrates contemporary literature regarding leukocyte changes in GH, examines the processes responsible for leukocyte-mediated vascular injury, assesses the therapeutic relevance of haematological indices, and underscores future research trajectories. Leukocyte-derived markers may function as economical supplementary tools for growth hormone risk classification, although necessitate disease-specific validation.