Maternal serum tumor necrosis factor-alpha in patients with preterm labor

OBJECTIVE: To evaluate maternal serum tumor necrosis factor-alpha (TNF alph a) levels in patients with preterm labor without clinical signs of chorioam nionitis and to compare these with levels in nonlaboring controls. STUDY DESIGN: The study group consisted of 44 patients with a singleton pre gnancy admitted to our department with the diagnosis of preterm labor betwe en 26 and 36 weeks' gestation. The control group consisted of 25 healthy co nsecutive patients with a singleton pregnancy without preterm contractions who were seen for routine antenatal visits. Maternal serum TNF alpha was me asured using a solid-phase, two-site chemiluminescent enzyme immunometric a ssay method, and levels were compared in patients with preterm labor and no nlaboring controls. RESULTS: The median maternal serum TNF alpha level for patients with preter m labor was 29.4 pg/mL (range, 12.3-173) as compared with 23 pg/mL (range, 11.9-62.7) in the control group (P = .031). Among 44 patients with preterm labor, 14 (32%) delivered within one week of admission. The median maternal serum TNF alpha level was significantly higher in patients who delivered w ithin one week than in those who delivered after one week and controls (71. 3 pg/mL [range, 28-173]) versus 22 pg/mL (range, 12.3-86) versus 23 pg/mL ( range, 11.9-62.7) (P < .0001). CONCLUSION: TNF<alpha> was elevated in patients with preterm labor, suggest ing a role for maternal serum TNF alpha in its initiation.