[Comparative studies of the venous system of the arm and leg before and after delivery]

Venous occlusion plethysmographic measurements were performed on the legs of ten non-pregnant subjects on ten consecutive days, in order to demonstrate the reproducibility of this method. In the third trimester of gestation and on the seventh day post partum, venous occlusion plethysmographic studies and vein caliber measurements were performed on arms and legs of 20 patients. A significant reduction in leg vein diameter following delivery was found. There were no differences in the diameters of arm veins measured in the third trimester and post partum. The results of venous occlusion plethysmography, as an indicator of venous function, revealed no differences between the third trimester and post partum in either the arm or the leg. Since hormonal changes during gestation must affect the entire venous system, i.e., also the arms and legs, mechanical displacement of the blood drainage pathways by the gravid uterus is most probably responsible for the significant dilatation of leg veins in the third trimester. A displacement of the higher sections of the femoral vein was demonstrated by Doppler sonography. Increased distensibility of the veins in the third trimester, continuing post partum, is probably the measurable basis of the much higher incidence of varicosis among women who have had children. It appears possible to detect extreme dilatations of leg veins sonographically, and to counter the increased risk of thrombosis and perhaps also to reduce the risk of later varicosis by timely compression treatment.