Acute effects of dihydralazine mesylate, furosemide, and metoprolol on maternal hemodynamics in pregnancy-induced hypertension.

The intervillous blood flow and other maternal hemodynamic parameters were assessed in 40 mothers with pregnancy-induced hypertension in late pregnancy before and after hypotensive treatment. Furosemide caused a significant decrease in the intervillous blood flow, whereas the effects of dihydralazine and metoprolol were both negative and positive, that is, more individual and diverse. These changes in the intervillous blood flow did not have any correlation with the changes in other maternal hemodynamic parameters. The importance of placental hemodynamic studies in the evaluation of hypotensive drugs is stressed.