Serum levels of human placental lactogen during and after prenatal dexamethasone therapy

Thirteen pregnant women were treated with 4 mg dexamethasone intramuscularly, three times daily, for seven days during the last trimester of pregnancy, in order to prevent the respiratory distress syndrome (RDS) in the neonate. Determination of human placental lactogen (HPL) was made daily during the treatment and at intervals of 2--3 days afterwards. No changes in HPL were seen during the treatment. One week after the treatment had been stopped, a statistically significant decrease in HPL was observed (p less than 0.01). The levels returned to normal during the following week. It is presumed, that the observed decrease in HPL may be regarded as a result of a direct depression of placental function caused by the dexamethasone therapy. The implications of this finding for the fetus are not clear, but in cases of placental insufficiency, glucocorticoid treatment should not be employed.