I want to take vitamin c as contraception. my period is due in 12 days. in what amounts should i consume vitamin c supplements to induce my periods?

Vit C contraception: It is not the dose that is important. For Vit C to prevent pregnancy you must hold the pill tightly between your knees all the time. No other way it can prevent pregnancy.

The C does not...: The C in vitamin C does not stand for Contraception. Vitamin C is plentiful in a normal person's balanced diet, which means normal people do not need extra vitamin C supplements. Vitamin C does not prevent pregnancy. Other vitamin supplements sold at the store also do NOT prevent pregnancy. Condoms sold at the store are excellent at preventing pregnancy.

Not birth control: Vitamin C is NOT a contraceptive. It cannot be relied upon to induce periods or prevent pregnancy. Please see your doctor to discuss reliable, effective birth control options.

If anything, it help: Vitamin C helps with collagen building. it is the opposite of what you want to achieve. It is not a birth control drug and it carries no contraceptive application. For a 20 year old lady, there are many choices in contraception, pills, patches, rings, IUDs with hormones and copper based. Some of them are preferable to others; I wish you the best. None of them is Vitamin C.