I will contact doctor about this but does anyone have knowledge / experience- my DD has had about 3 periods in the past year ( that is all she's ever had) , and nothing for 4 months. Her friend worried her saying it's because she's too thin. I don't think she's too thin, she is like I was at that age, a tall size 6/8.
I don't know if it helps but I am skinny always have been a size 6-8 and I didn't start until 15 but cannot recall how regular they were to start with. I know I was one of the last to start in my school year.
Thanks fad - she is completely developed, looks 16, and when I spoke to my gynaecologist in passing about it she said not to worry providing she was developing in other ways . However that was a year ago and I'm starting to think I should get it checked out.