- Identifies fetal and maternal structures or body parts and discover complications.
- No known risk.
- Done with full bladder.The client is to drink 6-8 glasses an hour and half before test and not to void.
- Results:
a. Biparietal diameter ( side to side measurement) of fetal head.
- 9.5 cm indicates a fetus of 40 weeks.
b. Head circumference and Femoral Length
- 34.5 cm indicates a 40 week fetus.
c. Doppler umbilical velocimetry
- measures the velocity at which Red blood cells in the uterine and fetal vessels are traveling.
- the systolic or diastolic ratio should fall to less than 3. If greater it is suggestive of hypertension.
d. Placental Grading
- based on the changes of the base of the placenta, placentas are graded as 0 (a placenta 12-24 weeks) ; 1 (30-32 weeks); 2 (36 weeks) ; and 3 (38 weeks).
e. Amniotic Fluid Volume Assessment. The measurement of 4 quadrants of amniotic fluid pockets detects abnormalities in volume associated with fetal disorder.
- the average amniotic fluid index (AFI) is 15 cm bet 28-40 weeks.
- an AFI greater than 20-24 cm indicates hydramnios, and an AFI less than 5-6 cm is oligohydramnios.
