ANTEPARTUM FETAL TESTING

M. Kamil

Goals of antepartum fetal testing◦To assess fetal well-being and prediction of future fetal condition

◦To prevent/ identify fetuses at risk◦Intrauterine death (IUD)◦Complications of intrauterine asphyxia

◦For early intervention to prevent IUD or complication of IU asphyxia

Tests◦Subjective maternal perception of fetal activity◦Fetal movement counting

◦Objective tests◦Non stress test (NST)◦Contraction stress test (CST)◦Biophysical profile (BPP)◦Umbilical artery blood flow velocity

1. Fetal movement counting◦Clinically important parameter of fetal wellbeing

◦ The EASIEST & MOST AVAILABLE

◦Assessed by mother subjectively

◦Number of movements “kick counts”/ hour

2. Non stress test (NST)◦Study the response of FHR to fetal movements.

TEST FOR FETAL CONDITION

Non stress test: Prep

Non stress test: Result◦Normal/R◦2 accelerations of the FHR in 20 min◦At least 15 beats above the baseline HR◦Last for at least 15 seconds

◦Abnormal/NR◦No FHR accelerations over a 40 min period◦Presence of decelerations with fetal movement

Non-stress test: Example

3. Contraction Stress Test◦Measure fetal response to a transient reduction in fetal oxygen delivery during uterine contractions

◦Induce with ◦Nipple stimulation◦ Infusion of dilute oxytocin solution 0.5 mU/min

TEST OF UTEROPLACENTAL FUNCTION

CST: Interpretation

Cunningham, F., & Williams, J. (2014). Williams obstetrics. (24th ed. / [edited by] F. Gary Cunningham et al. ed.). New York ; London: McGraw-Hill Medical.

NormalAbnormal

4.Biophysical profile (BPP)◦More accurate.◦ Consist 5 assessments

Cunningham, F., & Williams, J. (2014). Williams obstetrics. (24th ed. / [edited by] F. Gary Cunningham et al. ed.). New York ; London: McGraw-Hill Medical.

Fetal breathing

◦Characteristic:◦ Paradoxical chest wall movement

Cunningham, F., & Williams, J. (2014). Williams obstetrics. (24th ed. / [edited by] F. Gary Cunningham et al. ed.). New York ; London: McGraw-Hill Medical.

Interpretation of BPP

Cunningham, F., & Williams, J. (2014). Williams obstetrics. (24th ed. / [edited by] F. Gary Cunningham et al. ed.). New York ; London: McGraw-Hill Medical.

Modified BPP

◦The most predictive of outcome:

◦Non stress test

◦Amniotic fluid index

◦Most commonly used index: Systolic/diastolic ratio◦Quantify the flow velocity waveform.

5. Umbilical artery blood flow velocity

Conclusion◦Fetal well being assessment are important in all pregnancy.

◦AFT comprise few important tests that will benefit mostly towards high risk pregnancy.

◦Also important for monitoring the fetal condition and early detection of fetal abnormalities.

References◦ Beckmann, C., Herbert, W., Laube, D., Ling, F., Smith, R., & American

College of Obstetricians Gynecologists. (2014). Obstetrics and gynecology (7th ed.).

◦ http://www.uptodate.com/contents/nonstress-test-and-contraction-stress-test?source=see_link&sectionName=Nonstress+test&anchor=H10#H10

◦ Callahan, T., & Caughey, A. (2007). Blueprints obstetrics & gynecology (4th ed. / Tamara L. Callahan, Aaron B. Caughey. ed., Blueprints). Philadelphia ; London: Lippincott Williams & Wilkins.

◦ https://www.youtube.com/watch?v=NJEAQSyGmI0◦ http://www.uptodate.com/contents/nonstress-test-and-contraction-stress-te

st?source=see_link&sectionName=Nonstress+test&anchor=H10#H13◦ Cunningham, F., & Williams, J. (2014). Williams obstetrics. (24th ed. /

[edited by] F. Gary Cunningham et al. ed.). New York ; London: McGraw-Hill Medical.

◦ http://www.girldocs.com/obsterical/fetal-movement-counts/◦ https://www.uptodate.com/contents/decreased-fetal-movement-diagnosis-

evaluation-and-management?source=search_result&search=fetal+movement&selectedTitle=1~127

THANK YOU

CHOICE OF TEST◦ depends on multiple factors, including gestational age (up to

50 percent of NSTs are not reactive in healthy 24 to 28 weeks fetuses [47]), availability, desire for fetal biometry or follow-up of a congenital anomaly, ability to monitor the fetal heart rate (eg, the NST and CST may not be interpretable in a fetus with an arrhythmia), and cost.

◦Doppler assessment of the umbilical artery should be used to monitor the growth-restricted fetus, given its proven efficacy in reducing perinatal death in this setting when used with standard fetal testing (NST, BPP) and appropriate intervention [48]. It has only modest ability to predict fetal compromise in other high-risk pregnancies

◦ Antepartum Fetal testing◦Oligohydramnios & IUGR◦ Third trimester bleeding (Placenta Previa vs Placenta

Abruption)◦Molar Pregnancy◦ Cervical Cancer◦ Polycystic Ovarian Disease◦ Infertility