The result of transvaginal scan in 7w2d pregnancy.i have subchorionic hemorrhage of 1.7 x 2.42 x 1.12cm, lower uterine pole..how danger is that?

Usually ok: Subchorionic hemorrhages are very common, and they do not have to cause a miscarriage! you may have brown discharge that is probably old blood draining. If you had bright red bleeding, i would worry that the hemorrhage is active. But either way everything could be okay, so be optimistic. Let your doctor know if you have bright red bleeding or cramping.

Maybe OK since early: A subchorionic hemorrhage/hematoma is a bleed between the pregnancy and the uterine wall. It is an US finding, that if coupled with vaginal bleeding, can potentially increase the risk of miscarriage/preterm delivery, but w/out vaginal bleeding, it's hard to say. Size matters; worse if bigger (covering ~50% of placental bed) or occurring later. It can heal itself, but you just have to wait/watch.