Hii , Welcome To HCM & Thanks For Asking Your Query Here however a vaginal lump is rarely caused by Nuvarings ,but Common side effects of Nuvaring are vaginal infections and irritation,which may lead to a a vaginal abscess more specifically it may be a Bartholin s Abscess it can occur when Bartholin’s glands, located on either side of the opening of the vagina, becomes infected however a vaginal lump can be caused by many other medical conditions and as u did not mention any other symptoms like if there is any pain or discharge in lump , if you have fever or not , seriously it needs thorough medical check up and investigations to spot a confirm diagnosis i will strongly advise you to contact your Gynecologist, he will perform a physical examination to check for any lumps within the vagina your doctor may want to perform a biopsy on any masses found in the vagina to rule out other sources of the problem I hope it help Thanks & Get well Soon