Serial colour flow duplex scanning of the veins of the lower limb throughout pregnancy.

Objective: To examine changes in diameter and reflux in normal veins of the lower limb throughout pregnancy.

Methods: Fifty-seven women were recruited into the study and 43 completed the full assessment to six weeks postpartum. Thirteen had pre-existing venous disease and are reported elsewhere. The veins were assessed in both lower limbs using colour flow duplex scanning. This was performed at a 75 degree tilt measuring vein diameter and the presence or absence of reflux. Measurements were made at 12, 20, 26, 34, 38 weeks of gestation and 6 weeks postpartum.

Results: No new reflux developed in any of the veins studied. In the superficial system the maximum change was seen in the long saphenous vein at 34 weeks, on the left side the vein diameter failed to return to baseline size. Significant change also occurred in the superficial femoral vein. Dilatation of the deep veins of the calf was observed being greater in the left posterior tibial and the left peroneal at the mid-calf point.

Conclusion: Colour flow duplex scanning is an acceptable method of assessing the lower limb veins in pregnancy. Maximum diameter changes were seen in the long saphenous vein and in the deep veins at mid-calf. No new reflux developed during the gestation period in veins which were previously normal.