I have been on NuvaRing for almost three years now. Since I get all my prescriptions through an online pharmacy designated by my insurance, I have no immediate access to refills if I run out or lose a dose. I lost my NuvaRing last week on vacation and was unable to find it. It was in the third week of the 4-week cycle, and all instructions say to replace the ring within 7 days--but I don't have any more and am sure that I will not receive my refills in time. My boyfriend and I use backup protection anyway, so I am not as concerned with when to reinsert for maximum effectiveness--just when to reinsert once I get the refills so that I can start up the 4-week cycles again. None of the pamphlets or information tell me when to insert a new ring after more than two weeks of not having one.
If you are certain that you have not had any risky intercourse (condom slippage or breakage), you should insert the NuvaRing as soon as it is available. Just be sure to use condoms for the week following, at a minimum. If you are concerned about risk of pregnancy, then you should abstain from intercourse for 10 days and take a pregnancy test, prior to inserting the Ring.
The challenges with stopping and restarting a hormonal birth control method after a lapse, is that you might ovulate earlier (and be more fertile sooner) after stopping, and you might thus have interrupted or breakthrough bleeding. Light, brief breakthrough bleeding is not abnormal in these circumstances.
Lastly, note that Plan B IS available over the counter (assuming you are 18 yrs or older) in Washington. If you are a WWU student who is currently enrolled in classes this quarter, you can purchase Plan B here for $25. We also have a large supply right now of free Nuva Ring samples. Let us know if you need any further assistance.