Here's some info from 4 different websites about spider veins. They define spider veins as thin, crooked, reddish or purple lines on the skin.
http://www.health911.com/remedies/rem_vari.htm
Spider veins normally appear on the face, neck, upper arms or thighs and are often characterized by a small round, red spot with tiny red veins radiating outward like a spider's legs. This condition is known as spider angioma or spider telangiectasia. They are chronically dilated capillaries usually caused by excessive alcohol, medication, or elevated estrogen levels that occur during pregnancy, postmenopausal estrogen therapy, or perhaps exposure to estrogen-mimicking substances, such as petrochemicals and xenoestrogens derived from pesticides (Ed: this last possibility is a supposition on the part of this website only, and might be a cause if you have estrogen dominance or fibrocystic breasts). Quite often it occurs with cirrhosis of the liver.
This condition is harmless to your health, however some people want to treat it for cosmetic reasons. Spider veins can come and go. If you are undergoing estrogen therapy, consult with your physician about reducing the dose.
http://health.msn.com/centers/skincare/articlepage.aspx?cp-documentid=100150860
As for why women in particular get varicose veins, some additional and unique reasons that increase their risk include: Hormonal changes (puberty and menopause), birth control pills, post-menopausal hormone replacement therapy, and pregnancy (the greater the number the higher the likelihood). In fact, pregnancy-related varicose veins also can form around the vagina and anus (hemorrhoids).
While varicose veins may not cause any major symptoms, there are subtle clues as to their effects. These include:
• Dark blue and bulging veins just beneath the skin’s surface.
• Occasional swelling in the lower legs or ankles.
• Thin, purple lines on the skin (spider veins).
• A throbbing or achy feeling in the legs.
• Brown discoloration of the skin, especially noticeable around the ankles.
• A burning or itching feeling around the inflamed and bulging vein.
• Stasis dermatitis (skin breakdown) near the ankle due to poor circulation.
http://Www.4woman.gov/faq/varicose.htm#B
says:
Veins have valves that act as one-way flaps. These valves prevent the blood from flowing backwards as it moves up the legs. If the one-way valves become weak, blood can leak back into the vein and collect there. This problem is called venous insufficiency. Pooled blood enlarges the vein and it becomes varicose. Spider veins can also be caused by the backup of blood. Hormone changes, inherited factors, and exposure to the sun can also cause spider veins.
We suggest trying some of the remedies for varicose veins mentioned above, especially ones with bioflavonoids such as pycnogenol (PCO or OPC), quercetin and bromelain. If used regularly, horse chestnut, horsetail and witch hazel will prevent spider veins. Vitamin C will also be beneficial in your protocol. These supplements will help strengthen the integrity of the capillaries, reduce inflammation and aid in healing.
Some medications can cause spider veins. For example:
http://www.luhs.org/health/kbase/htm/mdx-/drde/2024/20/mdx-drde202420.htm
Nystatin and Triamcinolone(Topical): In the U.S.— * Dermacomb * Myco II * Mycobiotic II * Mycogen II * Mycolog II * Myco-Triacet II * Mykacet * Mykacet II * Mytrex * Tristatin II