Hi I Am 39 Years Olf. No Menstraul Cycle For

Hi i am 39 years olf. No menstraul cycle for 4 months & counting. Blood work & ultra sound came up normal. I am now being prescribed norethindrone 5 mg for 10 days then 2 more rounds after that to see if my body produces enough estrogen to start my cycle. I am terrified to take it. All reviews say "weight gain" amongst aniexty, depression, & as any steriod horomones higher risk of bloodclot, stroke.....well do i take it? I CANNOT & will not jeopardize my hard work to stay healthy/fit. I am not skinny but not fat. I will not be able to handle 15 extra lbs or depression or at worst a stroke. How do i know how this will affect me? Do you think i need it? What else can i do? Why does it make you gain weight if it did? I am confused. Other reports say its a diuretic....why do side effects happen to certain people? Body chemicals? Help me understand all of this. Thank you!!!