Association of IL-4 and IL-10 Polymorphisms with Preterm Birth Susceptibility: A Systematic Review and Meta-Analysis

Review question / Objective: The aim of our systematic review and meta-analysis was to summarize the effects of IL-4 and IL-10 gene polymorphism and clarify their possible association with PTB. Condition being studied: World Health Organization (WHO) defines preterm birth (PTB) as babies born alive before 37 weeks of pregnancy are completed. The new estimates show that the prevalence of PTB during 2014 ranged from 8.7% to13.4% of all live births, about 15 million preterm babies born each year. Besides, PTB is the leading cause of death worldwide for children below 5 years of age. Babies born preterm are at an increased risk of short-term and long-term complications attributed to immaturity of multiple organ systems, such as cerebral palsy, intellectual disabilities, vision and hearing impairments, and impaired cognitive development. PTB has become a worldwide public health problem, but its etiology remains unclear. Accumulating evidence shows that PTB is a syndrome that can be attributed to a variety of pathological processes(5). Inflammatory diseases and genetic background are known risk factors for PTB, many studies had shown that genetic variations in proinflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-1 α (IL-1 α) are associated with increased risk of PTB, but the relationship between genetic polymorphism in anti-inflammatory cytokines and risk of PTB remains controversial.