TISSUE INHIBITOR OF METALLOPROTEINASES - SERUM LEVELS DURING PREGNANCY AND LABOR, TERM AND PRETERM

Objective: To determine the levels in serum of tissue inhibitor of met alloproteinases (TIMP) in pregnancy and to examine the possibility of a time course in relation to parturition, both term and preterm. Metho ds: Serum tissue inhibitor of metalloproteinases was measured using an enzyme-linked immunosorbent assay. A cross-sectional study was conduc ted in 333 women during pregnancy, labor, and the postpartum period an d in 27 nonpregnant volunteers. Longitudinal data were obtained from 2 2 women who provided a sample at term, during labor, and in the postpa rtum period. Results: In uncomplicated pregnancies, serum TIMP levels were low from the onset of pregnancy until 37 weeks' gestation, in com parison to levels in nonpregnant women (P < .001). During the final we eks of pregnancy, levels rose and at 37-42 weeks were similar to nonpr egnant levels. The levels did not change with the onset of labor. Seru m concentrations of TIMP obtained during preterm labor were elevated c ompared to a control group of patients at a similar gestation who subs equently delivered at term (P < .01). Serum TIMP levels were significa ntly higher during the postpartum period than at all other times (P < .001). Conclusions: Changes in serum TIMP levels during and after preg nancy may parallel the remodeling of the extracellular matrix that tak es place throughout this period. Further work is necessary to evaluate the prognostic value of TIMP for preterm labor.