Which birth control is better nuva ring or mirena (levonorgestrel)? ...And in what ways?

Neither is "better". Both are effective for birthcontrol. Mirena (levonorgestrel) has to be inserted by your physician, but then lasts for up to 5 yrs. Most peoiple either don't have periods at all or shorter periods. If you decide to get pregnant it can be removed by your doctor at any time. Nuvaring is a vaginal ring which releases hormones at a constant dose. It must be changed monthly but is done by the patient.