The treatment of threatened premature labor by tocolytics, Ca++-Antagonists and anti-inflammatory drugs.

Prevention of premature labor is of considerable interest in research and clinics. Three groups of pharmacological agents can inhibit uterine activity: tocolytics, spasmolytics, and anti-inflammatory drugs. Tocolvtics like isoprenaline and fenoterol stimulate the beta-adrenergic receptors in decreasing the amplitude of contractions but with little effort on the muscle tone. Spasmolytic uterine inhibitors produce primarily a decrease in contraction frequency and tonus, and finally in high concentrations a decrease of the amplitude of contraction. An alteration of the electro-mechnaical coupling mechanism of the muscle cell via calcium antagonism is discussed. A combined application of both drugs, tocolytics and spasmolvtics, potentiates the inhibitory effect and may simultaneously reduce undesirable systemic and cardiovascular side effects. Anti-inflammatory agents of the acetylsalicylic acid or indometacin type reduce uterine activity by inhibition of prostaglandin synetheis and release. They are clinically used as complementary agents in case of unsuccessful tocolytic or spasmolytic inhibition of uterine activity. In our study only 21.4 per cent out of 603 cases of threatened premature labor justified a tocolytic treatment. Before attempting an inhibition one must decide on certain clinical parameters.