46 Obstetrics and Gynecology Board Review •••
❍ How are the various BPP parameters measured?
The presence of each parameter is given a score of 2 and the absence of each parameter is assigned 0 points.
❍ What must be present in order to receive 2 points for tone on the BPP?
One or more episodes of active extension/flexion of fetal limbs or spine, or an episode of opening and closing
of fetal hand.
❍ What must be present in order to receive 2 points for fluid on the BPP?
A cord and limb-free pocket of amniotic fluid measuring at least 2 × 2 cm.
❍ What must be present in order to receive 2 points for movement on the BPP?
Three or more discrete episodes of gross body movements or movements of extremities.
❍ What must be present in order to receive 2 points for breathing on the BPP?
One or more episode of rhythmic fetal breathing movements of 30 seconds or more.
❍ What components make up a modified BPP?
NST and amniotic fluid index (AFI). Necessary test to perform for the complaint of “decreased fetal movement”
in order to establish normal fluid volume.
❍ What is the false-positive rate of a well-performed BPP?
As low as 20%.
❍ What is the false-negative rate of a BPP?
0.8 per 1000 tests.
❍ What is the management of BPP scores?
- Score 8 to 10: Normal.
- Score 6: Equivocal. In a term fetus should prompt delivery, whereas in preterm fetus the BPP should be repeated
in 24 hours, and administration of steroids for lung maturity should be considered if <34 weeks. - Score 4: Indicates delivery should be warranted; vaginal delivery acceptable if fetal tracing allows for it.
- Score ≤ 4 : Indicates expeditious delivery usually by cesarean section.
❍ In the presence of risk factors, how often should the FHR be auscultated during the active phase of the first
stage of labor?
FHR should be evaluated and recorded at least every 15 minutes after a contraction.
❍ In the presence of risk factors, how often should the FHR be auscultated during the second stage of labor?
FHR should be evaluated and recorded at least every 5 minutes.
❍ What does an external FHR monitor measure?
Continuous Doppler detects cardiac valve closure.