Depression is one of the most universal of all human emotions. No one can expect to go through life without experiencing depressions. A depression brought about by sad events, failures, or financial reverses (and thus one which is entirely understandable) is sometimes referred to as a reactive depression. It is not always possible to identify the causes of depressions, however. Some seem to arise almost spontaneously from within; to put it another way, the events that trigger them seem to be insufficient causes. Some of the depressions that are seen in middle-aged individuals fall into this category and are sometimes referred to as endogenous depressions.
Some of the cyclic depressions to which women may be subject are essentially transitory. Their widespread occurrence suggests that they may depend on hormonal or other processes going on within the system. Thus the premenstrual tension and depression which affect a considerable number of women have been related to hormones with fluid-retaining properties. These psychic complaints appear with, and seem to be more marked in women who complain of considerable bloating and swelling. The depression often ends quite promptly with the onset of menstruation, at which time there is an abrupt drop-off in the hormones responsible.