To evaluate the Laser-Doppler flowmeter (LD) as a diagnostic tool in microcirculatory alterations of gestosis, cutaneous circulation was measured in the forearm under basal conditions and during reactive hyperaemia by means of an MBF3D (Moor Instrument Ltd., Oxford) in 11 hypertonic and in 14 normotonic pregnant women (+/- proteinuria, +/- pathologic increase in body mass, 16-36 years old, 26-40th week of gestation) with the exception of systolic and diastolic blood pressure, all statistical and clinical criteria were identical in the two groups. There were, however, in the hypertonic patients significant reductions in most of the LD criteria (basal and maximal speed and concentration of erythrocytes, duration of reactive hyperaemia). Regardless of group assignment, there were negative correlations between erythrocytes speed on the one side (basal, maximal), and blood pressure an the other, in some instances also to the increase in body mass and to the APGAR score of newborns. These preliminary findings are considered on an expression of cutaneous vasoconstriction accompanying hypertension in pregnancy. Extensive validation of LD under these conditions seems promising.