Skin perfusion in pregnancy.

Skin perfusion was monitored by photoelectric flow sensing in 42 pregnant and 20 nonpregnant women to obtain direct objective measurements of skin blood flow changes in pregnancy. The skin perfusion was found to increase significantly at the sixteenth gestational week and this increase was maintained at least 1 week post partum. The maximum increase, which was 3 to 4 times the control values, occurred between the twentieth and thirtieth week of gestation. No significant differences were found between normal and hypertensive pregnant patients, but significant decreases in skin perfusion were found in the supine position in patients with a positive "supine pressor test." These results indicate a pattern of increase in skin perfusion during pregnancy which appears to vary inversely with the reported increase in peripheral resistance.