Please let me know if there is a way to minimise the appearance of an anterior pelvic lift in a 16 year old girl?

Unclear what you mea. I'm not familiar with a "pelvic lift" that would be visible to the naked eye just looking at someone. Just a thought I had - has her back been screened thoroughly for scoliosis? Not just side to side curve, but front to back. Low back kyphosis (tilt) could cause it to look like pelvis is tilting forward. Just a thought.
Pelvic tilt. An anterior pelvic tilt is primarily a postural problem which is aggravated by sitting too much. See an orthopedist who can refer you to a physical therapist. Both of them can work out an exercise program for you.