a. Fetal Heart Sounds. The fetal heart begins beating by the 24th day following
conception. It is audible with a doppler by 10 weeks of pregnancy and with a fetoscope
after the 16th week (see figure 3-5). It is not to be confused with uterine souffle or
swishlike tone from pulsating uterine arteries. The normal fetal heart rate is 120 to 160
beats.
b. Ultrasound Scanning of the Fetus. The gestation sac can be seen and
photographed. An embryo as early as the 4th week after conception can be identified.
The fetal parts begin to appear by the 10th week of gestation.
Figure 3-5. Detecting fetal heartbeat.
c. Palpation of the Entire Fetus. Palpation must include the fetus head, back,
and upper and lower body parts. This is a positive sign after the 24th week of
pregnancy if the woman is not obese.
d. Palpation of Fetal Movement. This is done by a trained examiner. It is
easily elicited after 24 weeks of pregnancy.
e. X-ray. An x-ray will identify the entire fetal skeleton by the 12th week. In
utero, the fetus receives total body radiation that may lead to genetic or gonadal
alterations. An x-ray is not a recommended test for identifying pregnancy.
f. Actual Delivery of An Infant. Self-explanatory.
3-7.
TESTS UTILIZED TO DETERMINE PREGNANCY
a. Tests are based on the presence of human chorionic gonadotropin (HCG) in
the urine or blood.
(1) Urine. This test can be performed accurately 42 days after the last
menstrual period or 2 weeks after the first missed period. The first urine specimen of
the morning is the best one to use.
MD0921
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