How Often Do Veins Fade After Pregnancy?

It is difficult to know exactly when or if veins will improve after pregnancy.  I would encourage you to wait at least 6 months after pregnancy to try sclerotherapy.

Great questions. Veins do resolve after pregnancy because there is a hormonally-dependent association between spider veins and estrogen/progesterone.  This does not mean that you will not have any veins on the legs postpartum.  You may continue to have some veins that have progressed beyond the ability of the body to resolve them.  I would wait about 6 months after pregnancy to begin sclerotherapy or EVLT. 

Many changes occur during pregnancy including hormonal and increased volume as well as the pressure of the developing fetus on the pelvic veins. This results in stretching of the venous valves leading to increased venous back pressure and resultant stretching (refluxing) of the venous valves leading to spider and possibly varicose veins. It takes anywhere from 3 to 6 months post delivery for these changes to resolve and longer if breastfeeding. In addition, the valves may permanently malfunction. Prior to any treatment for the veins you should have a full venous evaluation with a reflux ultrasound. Your veins may resolve spontaneously but, if not, then see a vein specialist.

The pregnancy state places undue pressure on the deep veins and central veins - vena cava and illiac veins in the pelvis. When there is venous insufficiency, this pressure from the enlarging uterus causes the valves at the level of the groin to leak - venous insufficiency - and as a result, varicose veins form. Also, there is 30% more intravascular volume due to water retenstion during the pregnancy state, so this also causes varicose veins to form and stay distended. Once this pressure is gone (with delivery) and you lose the weight from water retention, some of the varicose veins (some) will fade and most will get smaller. So, wait 3-6 months if you are not nursing, or wait until you are done nursing, to get evaluated for treatment.

There is no "hard data' about 'how often do veins fade after pregnancy'.

It is always difficult to predict if the veins you have developed during pregnancy will resolve after.  In my opinion most always they do not go away and required treatment. 

Ideally, one should wait for 3-6 months post delivery to make the decision if they need sclerotherapy to address the problem areas and longer if breast feeding.