[Influence of fenoterol, ritodrine and clenbuterol on maternal oxytocin and PGFM levels].

In this investigation, the Oxytocin (OT) and 13, 14-Dihydro-15 Keto PGF 2-alpha (PGFM) levels were investigated in patients who required ripening of the cervix prior to induction of labour. Under randomized conditions four PGE2-Gel-groups and 1 Placebo group was formed. The patients who received PGE2-Gel were treated either with .4 mg PGE2-Gel intercervically without prior treatment with Betamimetica (n = 6) or 30 minutes prior to the application of .4 mg PGE2-Gel intercervically with 5 mb Fenoterol (n = 6) or 10 mg Ritadrine (n = 6) or 20 micrograms Clenbuterol (n = 6). These drugs were given by mouth. A control group of 6 patients received Gel without PGE2 Placebo. In previous investigations, it was shown that the Oxytocin level rises following the intercervical administration of PGE2-Gel to an unripe cervix whereas the PGFM level remains unchanged. Oral administration of Fenoterol inhibited the PG induced rise of the Oxytocin level and kept the Oxytocin level in the same range as following the administration of a Placebo. The present investigation served to check whether Ritadrine and Clenbuterol had an Oxytocin inhibiting effect as well as Fenoterol. It was found that administration of Betamimetica did not inhibit the ripening effect of PGE2-Gel on the cervix. Although labour did not start in 12 of 18 women treated with Betamimetica during four hours, the cervix ripened in the same manner as in women with labour. The administration of Placebo instead of PGE2-Gel showed no ripening effect (P less than 00001). Following the administration of Fenoterol the maternal heart rate increases significantly compared to Placebo.(ABSTRACT TRUNCATED AT 250 WORDS)