The value of menstrual suppression as an evidence of pregnancy is not, however, to be discounted to the extent that we might expect. This is true because the ailments which lead to confusion are relatively infrequent, and also because they exhibit characteristic symptoms which are foreign to pregnancy. Often these symptoms are obvious to the patient herself; if not to her, they will be obvious to her physician. It is about the doubtful cases, naturally, that a professional opinion is sought, and on that account physicians are perhaps inclined to overestimate the difficulty women have in learning for themselves whether or not they are pregnant. As a matter of fact, it is unusual for a prospective mother to fail to reach a correct decision--a decision for which she relies chiefly upon the suppression of her menstrual periods. It is doubtful whether menstruation ever continues after conception has taken place. Instances in which the menstrual function is believed to persist are not uncommon, and yet in all probability the discharge regarded as menstrual has a different origin. In most cases it should be interpreted as meaning that there is some danger of miscarriage. Since miscarriage often occurs about the time a menstrual period would ordinarily be expected, there is unusual opportunity for confusing the symptoms. At all events women err much more frequently in suspecting that they are pregnant than in overlooking the condition. Indeed, pregnancy is not likely to be overlooked unless menstruation has been irregular or suppressed for a month or more previous to conception. Thus, in the case of nursing mothers in whom menstruation is already suppressed and who are, moreover, deprived of certain evidence that the breasts give, pregnancy may sometimes advance several months before it is recognized. _The Changes in the Breasts_.--Various sensations in the breasts are accepted by women as a reliable sign of pregnancy; thus throbbing, tingling, pricking, or a feeling of fullness will be mentioned by one mother or another as having given her the first intimation that she was pregnant. A few women also find their breasts become tender immediately after they have conceived; this may be so marked that they cannot bear pressure. But unless such symptoms are accompanied by definite, visible changes, they have no value as signs of pregnancy. About the end of the second month the nipples become larger and more erectile, and deepen in color. The pigmented, circular area of skin which surrounds the nipple, called the areola, also darkens. The shade that the areola assumes will vary according to the complexion of the individual, growing darker in brunettes than in blondes. Ultimately, within this pigmented circle a number of elevated spots appear about the size of a large shot. These spots betray the presence of tiny glands always located there which, on account of the better state of nutrition during pregnancy, grow larger, and generally become visible.