My wife is 26 and we have a 17 month old little boy. She was in the bath tub and her upper thighs turned purple. This happened once during pregnancy and we thought it was just the way she was sitting and the baby had pressure on something limiting blood flow to her legs. The only area affected is from her mid thigh to her hip on both legs and this occurred again the other day. She developed 2 purple lines (looked like veins) six inches long on each side of her lower back about 1/2 inch wide. The purple color to her legs corrected itself in 30 minutes and the lines were gone by morning. She then had a tingling feeling in her arms the entire day following and went to the doctor. The doctor referred her to a neurologist and ordered several tests. Her blood work came back fine. I have researched this and cannot find anything. If you have any ideas of what could be wrong please let me know.