Hippocrates regarded the menstrual fluid like the blood of a slaughtered animal, or, in other words, blood.
Aristotle was of the same notion, comparing it to the blood which flows from a simple wound. It may be a question whether pure blood is discharged; but that the fluid contains the most important properties of blood, is a fact settled beyond dispute.
QUANTITY.
The quantity of menstrual discharge has been a matter of inquiry on the part of medical men.
It would be a very difficult task, if indeed, not impossible, to determine in any given case the precise amount of menstrual fluid discharged at a single period. An approximation to the general rule is all that can be reasonably looked for in investigations of this kind.
In cold regions, the discharge is more scanty; in hot, more profuse; and in temperate climates, a medium quantity is observed.
Dr. Gooch, in his “Treatise on Midwifery,” quotes De Haen as having made inquiries among poor women, who told him that they used only one cloth at the period, which, when wet, was dried, and then applied again. He then took a similar napkin, dipped it in blood, dried it, and applied the same. This experiment he tried repeatedly, and from it he deduced that from four to eight ounces, rarely ten, and most commonly about six, of the menstrual fluid, are lost at each period.
When we consider the great difficulty in ascertaining accurately the amount of menstrual fluid at a given period, and the great show which a comparatively small quantity of blood or menstrual fluid makes upon white, or light-colored clothing, it is not at all surprising that observers should have varied so much in regard to the true amount.
Hippocrates believed that the Greek women lost twenty pounds of blood at each menstrual period.
Galen estimated the quantity at eighteen ounces.