I had an appendix and an ovarian cyst removed 3 weeks ago. i should have seen my period last week wednesday but it still hasn't come. is this expected? when should i return to the hospital if it still doesn't come? i am not pregnant?

Removal of an ovarian cyst may also have removed a maturing ovarian follicle prior to ovulation, which will "reset" the cycle until another ovulatory follicle is stimulated, thereby delaying onset of the menstruation closest to the stated surgical procedure. If pregnancy is possible prior to the surgery, obtain a serum HCG test to be certain about pregnancy.

The question mark at the end of the last sentence makes me wonder about pregnancy. Pregnancy is considered with a late, missed, or scant period, and a positive pregnancy test. If you had no sexual intercourse since your last period, the delay in your expected menses may be due to your surgery. A trusted gynecologist can resolve this issue and advise regarding contraceptive options.