The time of confinement can never be accurately determined, because the onset of labor is purely an accident, dependent on many factors. Furthermore, conception does not take place necessarily at the time of intercourse, and we have no means of knowing whether conception occurred _just after_ the last period present or _just before_ the first period missed. So there is always a possible error of three weeks. Pregnancy in the human family normally lasts from 275 to 280 days, and the approximate date of confinement can be obtained by the following convenient rules: 1. Take the first day of the last menstruation, count back three months and add seven days. 2. Or, assuming that quickening occurs at the seventeenth week, count ahead twenty-two weeks from the day on which quickening was observed. 3. Or, count two weeks from the day of lightening. 4. Or, with a pelvimeter, get the length of the fœtus by Ahlfeld’s rule (measure from symphysis to breech of child, subtract two cm. for thickness of abdominal wall and multiply by two. The result is the length of the child in centimeters) and compare with fifty centimeters, which is the average length of a mature child. After the seventh month, the child in utero grows at the rate of about 1 cm. a week (0.9 cm.). 5. Or, by the tape, according to Spiegelberg’s standard of growth, as previously mentioned. The hygienic rules to be observed during pregnancy are founded on three basic principles: (1) To watch attentively the different organs and see that they functionate normally; (2) To eliminate all those conditions that favor the premature expulsion of the egg; and (3) To provide, so far as possible, for the normal gestation and the physiological delivery of the child. These factors will be taken up in detail. =The Diet.=—The appetite is usually somewhat increased, but it is unnecessary to indulge the stomach on the ground that the mother “must eat for two.” Longings, however, should be gratified so far as the demand is not for unwholesome things. Food should be simple and plainly cooked. Meat is permitted in moderation unless some organic change exists to contraindicate it. Rich pastries and gravies should be avoided, but cereals, fruits and vegetables should be used in abundance. It may be better to eat four times a day instead of three. Fluids should be taken freely, from one to two quarts daily. Milk is especially valuable, and alkaline, natural and charged waters, such as Vichy and seltzer, are useful. Wine, beer and other alcohols should not be taken, or if the patient is habituated to their use, the amount should be restricted on account of danger to the pregnancy and danger to the child.