101 days without my period, anybody else?

So has anyone ever gone a long amount of time without getting a period and found out what caused it? Me and my husband have been trying for almost a year now and I started having periods at 11 years of age (21 now) I have never missed a period in all those years until recently. I have not had a period since June and keep getting negative pregnancy test. My gyno put me on meds to kick start my period but that didn't help either. Please anyone with any input or advice would help tremendously!