Norethisterone isn’t really a drug that is meant for Long term use. More common uses for norethisterone is for example in dysfunctional uterine bleeding, delaying of periods and for endometrial protection when on estrogens. However common side effects include bloating and mood swings.
There are better alternatives if it is required for medium to Long term use eg the levonorgestrel releasing iucd (Mirena) or the oral contraceptive pill. Please discuss this with your gynae.