Any ideas why is it that I have really prominent veins in my hands?

Swollen hand veins. Hand veins can swell for many reasons but the most common is certainly hereditary . Other factors would be level of hydration, aging, sun exposure and loss of elasticity and volume. Actually, I am amazed at the amount of women that i see with bulging hand veins. They can be easily treated with laser or sclerotherapy and usually a combination of both.