[The influence of beta-mimetics on foetal pulmonary maturing (author's transl)]

Amniocentesis was carried out in 99 patients between the 31st to the 32nd gestational week in order to determine lung maturity. We subdivided the patients into 5 groups 11 women were treated with Hexoprenaline, 12 with Ritodrine, 26 with Dexamethason for acceleration of lung maturity, 23 with Dexamethason and beta-mimetics and 27 women were controls. A significant rise of surfactant factor measured by surface tension by means of the Wilhelmy-balance could be demonstrated in the two groups receiving glucocorticoids, whereas in the other groups the rise of surfactant factor corresponded with the usual increase due to age of gestation. But concerning the incidence and intensity of RDS and intensity, the best results were observed in the group with Dexamethason only. Increase of surfactant factor and incidence of RDS in groups with tocolytics and in the controls were similar, therefore we conclude, that beta-mimetics do not have an influence on lung maturity. A relatively high incidence of mild RDS-cases in the group of Dexamethason combined with tocolytics should be a warning to use both drugs routinely together.