Obstetric & Fetal Sonography measurement and normal value

Fetal Sonography Measurements

Obstetric & Fetal measurement and normal value

Normal Value

Fetal Meassurement Fetal Sonography Updated 2026 Educational Reference

Obstetric & Fetal Sonography — Measurable Structures

Gray Scale & Doppler Measurements (Short Form)

1. Early Pregnancy (First Trimester)

Gestational Sac (GS)

• MSD (mean sac dia.)
• GS volume
• Position

Yolk Sac

• Diameter
• No. / morphology

CRL (Crown-Rump Length)

• CRL (mm)
• Embryonic HR

NT (Nuchal Translucency)

• NT thickness (mm)
• NB (nasal bone)

Subchorionic Hematoma

• Size / volume
• % circumferential

2. Fetal Biometry (BPD, HC, FL, AC)

BPD (Biparietal Diameter)

• BPD (mm)
• OFD (occipito-frontal dia.)
• HC (head circumference)

FL (Femur Length)

• FL (mm)
• Other long bones (HL, humerus)

AC (Abdominal Circumference)

• AC (mm)
• Abdominal dia. (AP & trans.)
• UV diameter

EFW (Estimated Fetal Weight)

• EFW (Hadlock / Shepard)
• Percentile
• AC/FL ratio

Fetal Weight / Growth

• EFW percentile
• Growth curve plot
• Interval growth

3. Fetal Organs (Detailed / Anomaly Scan)

Fetal Brain

• LV width (atrial)
• Cisterna magna
• CM (posterior fossa)
• Cerebellar dia.
• TCD (trans. cerebellar dia.)

Fetal Heart

• Fetal HR (bpm)
• Cardiac: thorax ratio
• Aortic / pulmonary dia.

Fetal Kidneys

• Renal pelvis dia. (AP)
• Cortical echogenicity
• Renal length

Fetal Abdomen

• Stomach bubble size
• Bowel dilatation dia.
• Bladder volume

Fetal Thorax

• Chest circumference
• Lung lesion volume
• CVR (Chest Volume Ratio)

Fetal Skeleton

• Long bone lengths
• Foot length
• Nasal bone length

4. Amniotic Fluid & Placenta

Amniotic Fluid

• AFI (4-quadrant sum)
• Deepest pocket (cm)
• Subjective assessment

Placenta

• Position (anterior/post.)
• Grade (0-III)
• Thickness (mm)
• Placenta previa distance
• Cord insertion site

Umbilical Cord

• No. of vessels (3 / 2)
• Cord thickness / coiling index
• SUAc/PUAc assessment

5. Uterus & Cervix

Cervix

• Cervical length (mm)
• Funneling
• Internal os status

Uterus

• Wall thickness
• Fibroid size/location
• Scar thickness (LSCS)

Adnexa

• Corpus luteum size
• Adnexal mass size
• Ovary volume

6. Doppler (Fetal & Maternal)

Umbilical Artery (UA)

• PSV, EDV
• RI, PI
• S/D ratio
• End-diastolic flow (present/absent/reversed)

MCA (Middle Cerebral Artery)

• PSV (MoM)
• RI, PI
• Brain-sparing (MCA PI < UA PI)

Uterine Arteries (B/L)

• RI, PI
• Notching (early diastolic)
• Mean PI

Ductus Venosus (DV)

• Waveform (a-wave)
• PI
• Flow direction

Fetal Heart Rate

• FHR (bpm)
• Rhythm (regular/irregular)

Other Fetal Vessels

• Aortic / pulmonary flow
• UV flow (pulse)
• Renal artery RI