Yes, any women of any age can consider labiaplasty if she feels it’s necessary. Remember: the problem that labiaplasty corrects is the enlarged labia which causes physical discomfort or unhappiness because of its appearance. This surgery is done mainly to improve the appearance of the labia.
Until now there hasn’t been any medical evidence that suggests that surgical procedures like labiaplasty can interfere with childbirth at a later age or that you need to have had a child in order to have this surgery.