A controlled study of amniotic fluid immunoglobulin levels in intraamniotic infection.

The authors studied the levels of immunoglobulins (Ig) in the amniotic fluid of 46 patients with intraamniotic infection and of 46 matched controls. Amniotic fluid was collected through a transcervical intrauterine catheter. All infected patients had clinical signs of intraamniotic infection and at least 10(2) colony-forming units/milliliter of a high-virulence organism. None of the controls became infected. The matching criteria were gestational age, labor, interval from rupture of the membranes to delivery, and interval from rupture of the membranes to amniotic fluid collection. The authors tested each amniotic fluid sample for immunoglobulins G, M, and A by a single radial immunodiffusion technique. The mean IgG level in amniotic fluid for the intraamniotic infection group was 33.9 +/- 38.5 mg/dl, and the mean level for the control group was 17.9 +/- 11.1 mg/dl. The authors concluded that the mean IgG level in amniotic fluid from patients with intraamniotic infection is significantly higher than in controls (P less than .02).