Furthermore, gene expression analyses of various Th1 and Th2 cytokines in GCF (IL-1α, IL-1β, IL-8, and TNF-α) and in gingival tissue (IL-1β, IL-6, and TNF-α) during pregnancy and compared to postpartum with and without periodontal disease were not affected and could not be related to periodontal parameters such as bleeding scores [42, 43]. The gene discussed is TNF; the disease is periodontal disorder.