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PROBABLE SIGNS OF PREGNANCY
Probable signs of pregnancy are those signs commonly noted by the physician
upon examination of the patient. These signs include uterine changes, abdominal
changes, cervical changes, basal body temperature, positive pregnancy test by
physician, and fetal palpation.
a. Uterine Changes.
(1) Position. By the twelfth week, the uterus rises above the symphysis
pubis and it should reach the xiphoid process by the 36th week of pregnancy. These
guidelines are fairly accurate only as long as pregnancy is normal and there are no
twins, tumors, or excessive amniotic fluid.
(2) Size. The uterine increases in width and length approximately five times
its normal size. Its weight increases from 50 grams to 1,000 grams.
(3) Hegar's sign. This is softening of the lower uterine segment just above
the cervix. When the uterine is compressed between examining fingers, the wall feels
tissue paper thin. The physician will use bimanual maneuver simultaneously
(abdominal and vaginal) and will cause the uterus to tilt forward (see figure 3-1). The
Hegar's sign is noted by the sixth to eighth week of pregnancy.
Figure 3-1. Hegar's sign.
(4) Ballottement. This is demonstrated during the bimanual exam at the
16th to 20th week. Ballottement is when the lower uterine segment or the cervix is
tapped by the examiner's finger and left there, the fetus floats upward, then sinks back
and a gentle tap is felt on the finger (see figure 3-2). This is not considered diagnostic
because it can be elicited in the presence of ascites or ovarian cysts.
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