Ultrasound Monitoring of Ultrasound Monitoring of Fetal GrowthFetal Growth

By By

Dr. Khattab KAEODr. Khattab KAEO

Prof. & Head of Obstetrics and Prof. & Head of Obstetrics and Gynaecology Gynaecology

Faculty of Medicine, Al-Azhar University, Faculty of Medicine, Al-Azhar University, DamiettaDamietta

Fetal growthFetal growth::

Indications:Indications: Assessment of fetal Assessment of fetal growth is indicated in growth is indicated in conditions that may be conditions that may be complicated with growth complicated with growth problems e.g. PIH, DM, PPROM, problems e.g. PIH, DM, PPROM, APH, previous small/large baby APH, previous small/large baby and small/large for date uterus. and small/large for date uterus.

Timing:Timing: 3 3rdrd trimester. trimester.

Frequency:Frequency: Every 2-4w Every 2-4w according according to clinical circumstances.to clinical circumstances.

Technique:

- Check gestational age from a first trimester scan.

- Establish FHT and presentation.

- Trace the outer margin of the skull bone to measure the BPD & HC.

- Obtain the AC. Start - Obtain the AC. Start with a longitudinal with a longitudinal

view of the spine, then view of the spine, then rotate the transducer rotate the transducer through 90through 90 to obtain to obtain

the stomach & the the stomach & the intrahepatic section of intrahepatic section of

the umbilical vein.the umbilical vein.

The latter can not be obtained The latter can not be obtained when the spine being at the 12 when the spine being at the 12 o'clock position. Obtaining full o'clock position. Obtaining full

length of the vein means that the length of the vein means that the obtained section is too oblique. obtained section is too oblique.

The most accurate AC is the The most accurate AC is the smallest one obtained between smallest one obtained between

fetal respirations. The section fetal respirations. The section should be circular rather than should be circular rather than

elliptical (this can be produced elliptical (this can be produced by too much pressure by the by too much pressure by the

transducer). transducer).

A

D

B C

- Finally obtain the FL.

*Hadlock model utilizing *Hadlock model utilizing BPD, FL, HC & AC is the BPD, FL, HC & AC is the most accurate model. most accurate model.

**FL, HC & AC are better FL, HC & AC are better to be interpreted in to be interpreted in conjunction with the conjunction with the transverse cerebellar transverse cerebellar diameter measure. diameter measure.

B C

Low birth weight (LBW) = <2500 g infant whether born term or preterm. Small-for-date (SFD) fetuses = small for gestational age (SGA) = newborn that has a birth weight below the tenth centile for gestational age = constitutionally small fetuses and IUGR fetuses.

IUGR

An IUGR fetus is An IUGR fetus is the one that the one that failed to reach its failed to reach its growth potential, growth potential, even if still within even if still within the average birth the average birth weight centiles. weight centiles.

Diagnostic criteria should be based on both fetal size and placental function :

* When BOTH the anomaly scan and umbilical artery waveforms are NORMAL = “normal small fetus”. * When the anomaly scan is ABNORMAL and the waveforms are NORMAL = “abnormal small fetus”. * When the anomaly scan is NORMAL and the waveforms are ABNORMAL = “FGR”.

MacrosomiaMacrosomia

Grades: G1 4000-4499g G2 4500-4999g

G3 ≥5000g

Thank youThank you