Second-trimester amniotic fluid interleukin-10 concentration predicts preterm delivery

Abstract

Objective: Interleukin-6 (IL-6) is an inflammatory cytokine that has been shown to be elevated in the amniotic fluid of patients with preterm labor. On the other hand, interleukin-10 (IL-10) is an anti-inflammatory cytokine that has been shown to inhibit the synthesis of other cytokines. We hypothesized that amniotic fluid IL-10 in the early second trimester is low in patients who subsequently develop preterm labor, and because of its deficiency, excessive inflammatory responses associated with IL-6 elevation lead to preterm labor and delivery.

Study design: Amniotic fluid IL-6 and IL-10 levels were measured in 96 women who underwent genetic amniocentesis between 15 and 23 weeks' gestation. Levels of IL-6 and IL-10 were measured by immunoassay and correlated with demographic and pregnancy outcome information.

Results: Fifteen patients delivered at or before 36 weeks and 81 patients delivered after 36 weeks. There was an inverse correlation between amniotic fluid IL-10 concentration and gestational age at delivery. Similarly, an inverse correlation also existed between amniotic fluid IL-6 concentration and gestational age at delivery.

Conclusions: Both IL-10 and IL-6 levels in second-trimester amniotic fluid obtained at the time of genetic amniocentesis appeared to be higher in patients who subsequently developed preterm delivery. Therefore, low amniotic fluid IL-10 production during the second trimester does not seem to be an etiology for preterm labor.