Dark brown discharge for 8 days now...on nuva ring.

Hi,
Welcome to ehealthforum,
The dark discharge could suggest chances of pregnancy and probable implantation. The dark menstrual bleeding/periods/spotting could also indicate possibility of old oxidized blood (if you have had missed periods or delayed periods), hormonal changes, infections, endometritis, ovarian cysts, use of any medications, etc. The exact cause can only be made out after careful evaluation. Consider visiting your doctor/gynecologist at the earliest for thorough examination and further evaluation to look for the underlying cause for the abnormal dark vaginal bleeding that you describe. Treatment as appropriate (based on examination findings and investigations results) would be started to help you control the abnormal bleeding and regulate your periods. Consider being in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet and lifestyle. If infective cause is detected, and if you are sexually active, get your partner also treated simultaneously to prevent chances of re-infection, and avoid having intercourse while being on treatment.
Take care.