Amniotic fluid inflammation with negative culture and outcome after cervical cerclage.

Objective: To determine whether amniotic fluid (AF) inflammation, in the absence of infection, is associated with adverse pregnancy outcomes in nonelective cervical cerclage patients.

Methods: A retrospective case-control study was carried out. The patient population included 82 singleton pregnancies with negative AF cultures. The variables used to define AF inflammation were white blood cell count (WBC) >50 cell/mm(3), glucose <14 mg/dl or interleukin-6 (IL-6) >11.3 ng/ml. The study group consisted of cases with intra-amniotic inflammation. Sub-analysis was performed for the groups in which IL-6 concentrations were measured. Adverse outcomes were evaluated with variables such as gestational age at delivery, interval from cerclage to delivery, chorioamnionitis and cumulative neonatal morbidity.

Results: Elevated AF WBC was correlated with severe and extreme preterm delivery (p < 0.05). Decreased AF glucose was associated with histological chorioamnionitis and a decreased cerclage to delivery interval (p < 0.05). Elevated AF IL-6 correlated significantly with decreased gestational age at delivery (p < 0.012) and decreased cerclage to delivery interval (p < 0.001). Elevated IL-6 concentrations were associated with severe, extreme preterm delivery (p < 0.001) and neonatal death (p < 0.001).

Conclusion: Elevated AF IL-6, elevated WBC and low AF glucose, in the absence of a positive AF culture, are significantly associated with adverse pregnancy outcomes in patients undergoing nonelective cerclage.