THE INFLUENCE OF TOCOLYTIC THERAPY ON SERUM DIGOXIN-LIKE IMMUNOREACTIVE SUBSTANCE CONCENTRATION

Digoxin-like immunoreactive substance (DLIS) has been proposed to have a role in what seems to be the timely onset of labor. The relationshi p between the DLIS in patients with preterm labor and the success of t ocolytic therapy with ritodrine and nifedipine has been studied. Using a commercially available radioimmunassay kit, DLIS levels were determ ined in a total of 47 women with preterm labor and in 30 control. Toco lysis was successful in 37 of 47 women, in 20 of whom nifedipine and i n 17 ritodrine was the tocolytic agent. Mean DLIS concentration was hi gher in patients with preterm labor. Moreover, DLIS levels were found to be decreased by successful tocolysis as could be observed from the values before initiation of tocolytic therapy and on the 3rd day of to colysis for both nifedipine (0.268 +/- 0.198 vs. 0.220 +/- 0.210 ng/ml ) and ritodrine(0.250 +/- 0.176 vs. 0.196 +/- 0.147 ng/ml; Wilcoxon te st, p < 0.05).