Softening of the lips of the os (Goodell’s sign) may be found, but it must not be confused with erosions of the os. The os of a nonpregnant woman feels like the tip of the nose, and that of the pregnant woman like the lips.

Fig. 26.—Bimanual examination. (Edgar.)

The increased size and globular shape must also be considered as confirmatory.

Hegar’s Sign.—The upper part of the uterus is soft and distended by the ovum, the lower part is soft and not filled out by the ovum. Between the two is an isthmus that is compressible between the fingers of one hand in the vagina, and of the other upon the abdomen. When found, this sign is of great value.

At the eighth week, pregnancy can be regarded as highly probable by the conjunction of the following symptoms and signs: Amenorrhœa, morning sickness, irritability of bladder, slight breast changes in primiparas, lips of os externum softened, uterine body enlarged, softened, and nearly globular in shape, and Hegar’s sign.

Abderhalden’s test is a serum reaction based on the well established principle that the introduction into the blood of an organic foreign substance leads to the formation of a ferment to destroy it. Abderhalden’s plan was to discover whether the blood of a pregnant woman contained a ferment capable of destroying placental protein. It is a very complicated test, and subject to many inaccuracies and numerous sources of error. At the same time, the main features of this reaction have been confirmed, and when it is worked out, it will be of immense value not alone in early uterine pregnancies, but in extrauterine pregnancy. This view very properly demands that pregnancy be regarded as a parasitic disease. It is practicable as early as the sixth week to make a diagnosis, and it only fails in possibly ten per cent of the cases. The negative test is equally definite as eliminating pregnancy.

Sixteenth Week.—Morning sickness and urinary symptoms have disappeared but amenorrhœa remains. Enlargement of the breasts is noticeable, as well as the increased pigmentation. The uterus begins to rise above the symphysis as an elastic, somewhat ill-defined, boggy mass. The cervix is softer. The characteristic dull lavender coloration of the vulvar mucous membrane is now evident. It is due to the congestion and is called Jacquemins’ sign.

Two New Signs.—Irregular, painless contractions of the uterus (Braxton Hicks’ sign), and ballottement.

The contractions of Braxton Hicks now become more easily palpable.