Is it normal for a 14-year-old girl not to have her period?

Generally, the girls begin puberty between ages 8 and 15. If there is delay in puberty, the girl may have delayed menstruation.
One of the most common cause of delayed puberty in girls is lack of body fat. Being too thin can disrupt the normal process of puberty.
Consult doctor if she hasn’t any sign of puberty.