a girl 17 hasn't had a period what is wrong
Nothing happens seven years after a girl has her period. There's nothing specific about this length of time.
Yes, she is.
its just a sign
if you mean when a girl has her period, this happens once a month once the girl reaches puberty.
Nothing.
Menopause means a stopping of having periods. There IS no period blood.
If a girl has her period it all she is not pregnant. Irregularities in when the girl starts her period are a natural phenomena. the only way to control is, is by using the anticonception pill, but "the girl" has to see her doctor about that.
Around 12 yrs.
She starts her period
usually 6 months or so
No. Hormones determine when that happens.