How Does The Norethisterone Tablet Affect The Periods?

I am a 25yr old mom of two, slightly over-weight with one cot-death and one abortion on my record.
My doctor prescribed me Norethisterone to kick-start my periods after being on the depo injection after the abortion, two years ago, but everything Ive read is telling me that this pill doesnt start periods, it stops them. is this right?