Is the character of milk modified materially by outside conditions that influence the mother? There is great diversity of opinion upon this subject. Two writers make such contradictory statements as the following: "Age has little influence. Illness, menstruation, pregnancy, fever, and even severe emotional disturbances are almost entirely devoid of any appreciable effect on the composition of the milk" (Hutchison).

1 Jul. American Medical Association, 1910, Oct. 10, 1212.

"Women are especially sensitive, and when living in the midst of our modern civilization, so harmful for the production of good nursing, present an aggravated example of disturbance of the mammary glands" (Rotch). Both of these statements are probably correct. It is true that some, probably many, women near the menopause suckle their babes successfully, as may also those suffering for the necessities of life and those who are under severe nervous strain or who have severe or chronic illness; but not all women can do so under such conditions. Measuring the quality of the milk by the results of the nursing as manifested by the growth of children, the milk of these mothers must be called good. On page 70 will be found a series of analyses of human milk made for Rotch, which show the wide variation of its composition. Upon each of these kinds of milk healthy children were reared. It is quite possible, therefore, for some infants to thrive upon poor milk that would be harmful to others, or would, at least, be deficient. It is also quite true that for weak babes, and especially for those who are under the physician's constant watch, milk that deviates much from certain standards of composition is sure to provoke illness.

To a limited extent the quantity of a mother's milk can be increased by administering to her more water than she habitually drinks. It can be reduced by withholding water and by withdrawing serum from the blood - as, for instance, by purgation or by acute enteritis. Drugs, such as belladonna, have a similar effect by lessening the activity of the mammary glands.

The eating of carbohydrate and fat by mothers does not modify their milk. An abundant consumption of proteins, however, increases the percentage of fat in it. This is the only ingredient of milk that can be influenced by diet. Tea, coffee, cocoa, and beer, wine, and other alcoholics have no influence upon the secretion of milk, except as the water in them may increase the quantity, if sufficient be taken.

If an infant is put to the breast too often, it stimulates the secretion of milk and renders it richer in protein. The practice followed by many mothers of giving the breast to their babes whenever they cry is wrong. As such crying is generally caused by colic resulting from an excess of protein in the milk, and as the practice referred to increases still more the protein contents of their milk and lessens its digestibility, it is evident that under such circumstances the infants should be nursed less frequently rather than with increased frequency. The protein contained in milk can be lessened to some extent if a mother will exercise daily to the point of moderate weariness. The average wet-nurse or mother should walk out-of-doors for one or two hours a day, preferably half the time in the morning and half in the afternoon. This will mean walking, all told, a distance of from three to four miles a day. It is probable that the weakness of the mother and the consequent lack of exercise accounts for the excess of protein in mother's milk and the period of colic that so many babes have during the second and third months of life. Wet-nurses often find their milk affected unfavorably, the result, no doubt, of a change from a life of labor to one of relative luxury and comparative inactivity.

Menstruation does not always change the character of a woman's milk. During the first, and sometimes also during the second, menstruations after childbirth a slight digestive disorder lasting two or three days may occur. After this, the infant feels the disturbance little or not at all. In other instances indigestion is excited each month for a few days during the mother's menstrual period. In rare cases the reestablish-ment of menstruation so modifies the mother's milk as to make it necessary to use some substitute more stable in composition.

Pregnancy of a mother is usually regarded as a reason for weaning a nursling, and rightly so, for few women have the strength to nurse a baby and develop a fetus at the same time. Moreover, lactation cannot be maintained continuously. A period of rest must be obtained to insure the ability to suckle the coming infant. The constant irritation of the mammary glands by nursing has occasionally been thought to produce abortion.

The influence of diet and exercise upon the secretion of the mammary glands has led Rotch to formulate the following rules:

To increase the total quantity of milk: (a) Increase proportionately the amount of liquids in the mother's diet; and (b) encourage her to believe that she can nurse her infant.

To decrease the total quantity: Decrease proportionately the amount of liquids in the mother's diet.

To increase the total solids: (a) Shorten the nursing intervals; (b) decrease the mother's exercise; (c) decrease the proportion of liquids in her diet.

To decrease the total solids: (a) Prolong the nursing intervals; (b) increase the mother's exercise; (c) increase the proportion of liquids in her diet.

To increase the fat: Increase the proportion of meat in her diet.

To decrease the fat: Decrease the proportion of meat.

To decrease the proteins: Increase exercise up to the limit of fatigue.