Serum macrophage migration inhibitory factor in the prediction of preterm delivery

OBJECTIVE: Macrophage migration inhibitory factor is a soluble mediator that helps govern the interaction between cytokines and stress hormones (eg, cortisol). We determined whether maternal macrophage migration inhibitory factor levels predicted subsequent preterm delivery. STUDY DESIGN: A nested case-control study measuring serum macrophage migration inhibitory factor concentration at 9-23 weeks' gestation in women who ultimately delivered preterm (n = 60) compared with control women who delivered at term (n = 122). We also examined the connection of macrophage migration inhibitory factor with self-reported psychosocial variables. RESULTS: Macrophage migration inhibitory factor was elevated in the preterm delivery cases (P = .0004), and log macrophage migration inhibitory factor concentration showed a graded response relationship with likelihood of preterm delivery. High-macrophage migration inhibitory factor was also associated with maternal risk-taking behavior, which itself was a risk factor for preterm delivery. Macrophage migration inhibitory factor remained associated independently with preterm delivery after adjusting regression models for several other preterm delivery risk factors (odds ratio, 3.11, 95% confidence interval, 1.54-6.30). CONCLUSION: High-serum macrophage migration inhibitory concentration in early to midpregnancy is linked with subsequent preterm delivery.