Hypothalamic Amenorrhea. Amenorrhea simply means the absence of menstruation (one or more missed menstrual periods), and it can be caused by a variety of things, including problems with the reproductive organs or hormones.
Normality is an ambiguous measure of the concentration of a solution. It needs a definition of the equivalence factor, which depends on the definition of equivalents. The same solution can possess different normalities for different reactions.
definition : orthogonality In mathematics, orthogonality is the relation of two lines at right angles to one another (perpendicularity), and the generalization of this relation into n dimensions; and to a variety of mathematical relations thought of as describing non-overlapping, uncorrelated, or independent objects of some kind.