I am 45 year now and i missed my period for 5 months notice the linea nigra on my stomach and i am not pragnant what is the meaning of that?

Lines nigra: Linea nigra is a vertical brown mark on the abdomen common in pregnancy in women that tan easily. It is due to a circulating hormone called melanocyte stimulating hormone or MSH. In non-pregnant women a hormonal disorder could be responsible. Best to see your doctor for consultation, examination and tests, including those for Addison disease.

Menopause: A woman at the age of 45 y/o, who missed her menstrual period for several months could be in menopause and never have a menstrual period again.