AMNIOTIC-FLUID INTERLEUKIN-10 CONCENTRATIONS INCREASE THROUGH PREGNANCY AND ARE ELEVATED IN PATIENTS WITH PRETERM LABOR ASSOCIATED WITH INTRAUTERINE INFECTION

OBJECTIVE: To better understand the role of the antiinflammatory cytokine interleukin-10 in preterm labor and infection, we evaluated the amniotic fluid interleukin-10 concentrations through pregnancy, in term, and in preterm labor. STUDY DESIGN: Amniotic fluid interleukin-10 levels were measured in 147 women throughout pregnancy including patients in the second trimester, patients at term with and without labor, and in patients in preterm labor with and without an intrauterine infection. We compared the amniotic fluid interleukin-10 concentrations among these five groups using the Mann-Whitney U test. RESULTS: Amniotic fluid interleukin-10 was detected in 70% to 91% of patients in each of the five study groups. Higher concentrations were found at term compared with the second trimester (p < 0.001) and concentrations were significantly greater in patients with preterm labor and intrauterine infection compared with those patients in preterm labor without infection do < 0.001), patients at term in labor (p < 0.001), or patients at term not in labor (p < 0.001). When the patients in preterm labor with infection were analyzed by gestational age, those patients at < 30 weeks had significantly higher amniotic fluid concentrations of interleukin-10 (p = 0.014). CONCLUSIONS: Interleukin-10 was present in the amniotic fluid of the majority of pregnancies, with higher concentrations found at term compared with the second trimester. Intrauterine infection was associated with significantly increased concentrations, with even higher concentrations found in the very premature pregnancies. Interleukin-10 has a prominent yet undefined role in pregnancy and preterm labor complicated by intrauterine infection.