areolae, and the mid-line of the belly, become darker; brown flecks (lentigo) tend to appear on the forehead, neck, arms, and body; while striae—­at first blue-red, then a brilliant white—­appear on the belly and thighs, though these are scarcely normal, for they are not seen in women with very elastic skins and are rare among peasants and savages.[173] The whole carriage of the woman tends to become changed with the development of the mighty seed of man planted within her; it simulates the carriage of pride with the arched back and protruded abdomen.[174] The pregnant woman has been lifted above the level of ordinary humanity to become the casket of an inestimable jewel.

It is in the blood and the circulation that the earliest of the most prominent symptoms of pregnancy are to be found.  The ever increasing development of this new focus of vascular activity involves an increased vascular activity in the whole organism.  This activity is present almost from the first—­a few days after the impregnation of the ovum—­in the breasts, and quickly becomes obvious to inspection and palpation.  Before a quite passive organ, the breast now rapidly increases in activity of circulation and in size, while certain characteristic changes begin to take place around the nipples.[175] As a result of the additional work imposed upon it the heart tends to become slightly hypertrophied in order to meet the additional strain; there may be some dilatation also.[176]

The recent investigations of Stengel and Stanton tend to show that the increase of the heart’s work during pregnancy is less considerable than has generally been supposed, and that beyond some enlargement and dilatation of the right ventricle there is not usually any hypertrophy of the heart.

The total quantity of blood is raised.  While increased in quantity, the blood appears on the whole to be somewhat depreciated in quality, though on this point there are considerable differences of opinion.  Thus, as regards haemoglobin, some investigators have found that the old idea as to the poverty of haemoglobin in pregnancy is quite unfounded; a few have even found that the haemoglobin is increased.  Most authorities have found the red cells diminished, though some only slightly, while the white cells, and also the fibrin, are increased.  But toward the end of pregnancy there is a tendency, perhaps due to the establishment of compensation, for the blood to revert to the normal condition.[177]

It would appear probable, however, that the vascular phenomena of pregnancy are not altogether so simple as the above statement would imply.  The activity of various glands at this time—­well illustrated by the marked salivation which sometimes occurs—­indicates that other modifying forces are at work, and it has been suggested that the changes in the maternal circulation during pregnancy may best be explained by the theory that there are two opposing kinds of secretion poured into the blood in unusual degree during pregnancy:  one contracting the vessels, the other dilating them, one or the other sometimes gaining the upper hand.  Suprarenal extract, when administered, has a vaso-constricting influence, and thyroid extract a vasodilating influence; it may be surmised that within the body these glands perform similar functions.[178]