A number of ailments of which prospective mothers may complain do not require treatment with medicine. This, however, will not be taken to imply that there is no need to consult a physician. On the contrary, and it cannot be emphasized too strongly, the prospective mother should _seek professional service whenever there is anything about her condition she does not understand_. Sometimes, when she thus consults the physician, he will explain to her that what she has noticed is merely one of the natural manifestations of pregnancy and that she can have no control over it; at other times he will suggest changes in her mode of life which will very likely afford her relief. The frequency with which physicians find that ailments may be corrected by the adoption of hygienic measures indicates that such ailments are more often due to ignorance or carelessness than to the existence of disease. NAUSEA AND VOMITING.--We have already learned that nausea, especially in the morning on rising from bed, frequently corroborates the suspicion of a woman that she has become pregnant. So commonly, indeed, is this symptom expected that most women take no account of it other than as an evidence that they have conceived, and consequently do not complain of it. A few who have heard the old adage, "a sick pregnancy means a safe one," which incidentally is not correct, actually accept nausea as a favorable sign. In other cases the nausea is not to be dismissed so lightly; and a relatively small group of patients suffer from persistent vomiting. When prospective mothers are questioned systematically, it appears that at least one- half and perhaps two-thirds of them experience more or less discomfort from sick stomach. Generally this begins shortly after a menstrual period has been missed and ceases six or eight weeks later; it persists occasionally until the movements of the child have been perceived. Nausea and vomiting are limited, in the vast majority of cases, to the early morning, but some patients are annoyed only after meals, and a few at irregular intervals during the day. The fact that the attacks do not always appear at the same time, and that they differ in severity, indicates that different causes may be concerned in their production. And it is true that there are several kinds of vomiting that occur during pregnancy, although the classification interests only physicians. The laity, however, should understand that the treatment of any given case will vary according to the class to which it belongs, and therefore the occurrence of troublesome vomiting should be promptly reported to the physician.