Amniotic fluid CA-125 as a marker of intra-amniotic inflammation associated with preterm delivery: a preliminary single center study.

OBJECTIVE

The purpose of this study was to investigate whether amniotic fluid (AF) CA-125 in patients with preterm labor or preterm premature rupture of membranes can help predict intra-amniotic inflammation (IAI), microbial invasion of the amniotic cavity (MIAC) and imminent delivery.

METHODS

We recruited 36 women who admitted with impending preterm delivery and suspicious AF infection. AF matrix metalloproteinase-8 (MMP-8), white blood cell (WBC) count, glucose levels, and CA-125 levels were measured, and the MMP-8 bedside rapid test was also performed. AF culture and PCR were subsequently performed to confirm MIAC. We compared AF CA-125 levels according to the presence of IAI or MIAC and assessed its predictive value for delivery within 7 days of admission.

RESULTS

AF CA-125 levels were significantly higher in the IAI group than in the non-IAI group (mean ± standard deviation: 5608 ± 864 vs 904 ± 84 IU/ml; p = 0.001). AF CA-125 levels showed a negative correlation with gestational age and a positive correlation with AF WBC counts and MMP-8 levels. AF CA-125 levels were higher in the MIAC group, though this difference was not statistically significant (p = 0.064). Delivery within 7 days of admission was significantly more common in patients with higher AF CA-125 levels (cut-off: 1650 IU/ml, sensitivity: 71.4 %, specificity: 86.4 %, p = 0.005).

CONCLUSION

AF CA-125 levels are increased in patients with AF inflammation and can be a predictor of imminent preterm delivery.