Hi.
I had missed periods after my surgery also.
On February 4th this year, I had a temporary ileostomy placed on me.
Two weeks after the surgery I had spotting but after that, I didn't have a period for two month's.
My ileostomy was reversed on April 6th & 3 weeks after this surgery, I had a mentrual cycle again. I asked my doctor about the missed periods & she said this is due to chemical changes occuring in your body. My doctor also said majority of women who have surgeries go through this.