=2. Changes in the size, shape and consistency of the uterus= which take place during the first three months of pregnancy are very important indications. These are discoverable upon vaginal examination, which shows the uterus to be more ante-flexed than normal, considerably enlarged, somewhat globular in shape and of a soft, doughy consistency. About the sixth week the so-called _Hegar’s sign_ is perceptible through bimanual examination, the fingers of one hand being pressed deeply into the abdomen, just above the symphysis and two fingers of the other hand passed through the vagina until they rest in the posterior fornix, behind the cervix. The lower segment of the uterus, which may be felt between the finger tips of the two hands, is extremely soft and compressible. This sign, named for the man who first described it, is one of the most valuable signs in early pregnancy. =3. Softening of the cervix= occurs, as a rule, about the beginning of the second month. In some cases, such as certain inflammatory conditions and in carcinoma, this sign may not appear. =4. Painless uterine contractions=, called _Braxton Hicks_ from their first observer, begin during the early weeks of pregnancy and recur at intervals of five or ten minutes throughout the entire period of gestation. The patient is not conscious of these contractions, but they may be observed during the early months by bimanual examination, and subsequently by placing the hand on the abdomen. One feels the uterus growing alternately hard and soft as it contracts and relaxes. But all of the probable signs of pregnancy, like the presumptive symptoms, may be simulated in non-pregnant conditions; hence the appearance of any one of them alone may not be deeply significant. But two or more occurring coincidently constitute strong evidence of pregnancy. =The positive signs of pregnancy=, of which there are three, are not apparent until the 18th or 20th week, and all emanate from the fetus. =1. Hearing and counting the fetal heart beat= is unmistakable evidence of pregnancy. The sound of the fetal heart beat is usually likened to the ticking of a watch under a pillow. The rate is from 120 to 140 per minute, being about twice as fast as the maternal pulse. So long as its rhythm is regular, however, the rate may drop to 100 or increase to 160 beats per minute without being considered abnormal, or indicative of trouble with the fetus. =2. Ability to palpate the outline of the fetus= is also a positive sign of pregnancy, if the head, breech, back and extremities are unmistakably made out through the abdominal wall.