Effects of betamethasone on plasma levels of estriol, cortisol and HCS in late pregnancy.

The effect of a single dose of betamethasone on the maternal plasma concentration of estriol and cortisol was studied. The concentration of estriol decreased rapidly. A maximal suppression of about 70 per cent was seen after 6-24 hours. A similar influence on the maternal plasma concentration of cortisol was observed. HCS (human chorionic somatomammotropin) was not influenced by betamethasone. These facts have to be taken into consideration after treatment with synthetic corticosteroids in high risk pregnancies.