I'm mid-to-late 40s and periods have slowed way down. am i considered menopausal after only 12 months with no p, or should i use 24 months as a guide, since i'm under age 50?

Although there are tests to document the presence of menopause, in my opinion most women know when menopause has appeared regardless of age. Apparently you're not experiencing hot flashes at this time & don't require treatment. Your gynecologist can advise you further.

"True" menopause is defined as no ovulation, which is delayed in 40's and early 50's, causing "irregular" bleeding episodes. Sustained production of elevated estrogen by the ovaries results in breakthrough bleeding without ovulation. Ask your GYN physician about low dose oral bcps, which normalize this process by stopping ovarian production of estrogen.