1. Fetal Biometry

2. Embryonic/fetal growth 1st trimester
Crown rump length best index of gestational length
Phase of most rapid growth in length (up to first ½ preg.)
Time when growth influenced most by
genome aneuploidy
external influences infection
drugs
Stage being set for later effects smoking
maternal nutrition
uterine circulation

3. Environment (diff. populations and over time)
Fetal Growth 2nd – 3rd trimesters Why has it happened what will be the best tests?
Environment (diff. populations and over time)
maternal factor small maternal size (customise)
smoking-dose dependent (200g)
parity
preeclampsia
previous FGR
glucose concentrations

4. Measurement of BPD Short midline, 90 degrees to the beam Oval shape
Thalami
NO cerebellum or orbits
Cavum septum pellucidi
Measure from outer bone to inner bone at widest point (parietal eminence)

5. Measurement of BPD

6. Measurement of HC Short midline, 90 degrees to the beam Oval shape
Thalami
NO cerebellum or orbits
Cavum septum pellucidi
Measure circumference of outer bone (usual to put calipers at occiput then sinciput)

10. Measurement of AC Transverse section through abdomen
As round as possible
Transverse spine and short length 1 rib
Stomach
Short length umbilical vein and right portal vein approximatly 1/3 from anterior abdominal wall
NO kidney, bladder, heart. Adrenal allowed

11. Measurement of AC

12. Measurement of FL Full length femur Bone 90 degrees to the beam
Both ends clearly seen
Skin line separate and beyond bone end
Measure from bottom of ‘U’ either end
Bring in calipers from wider point to end

13. Measurement of FL

14. Summary of fetal growth prediction of IUGR
Poor predicitors of IUGR
Single estimates of fetal size
AFV
Umbilical artery resistance (doppler)
Useful
fetal abdominal area (AC)
fetal growth velocities
Owen et al BJOG 2003;

17. Pathophysiological factors and clinical conditions
Preeclampsia FGR
APS,uterine abns,plac infarct
Malnutrition
Altitude, anaemia,cyanosis
Placental Failure
Reduced utero/plac blood flow
Small surface area
Altered Maternal Substrate
Hypoglycaemia
Hypoxia

18. Reduced fetal drive
Chromosomal anomalies
Gene defects
Endocrine disorders
Fetal anomalies
Extnal/int.growth inhibition
Drugs, smoking age, infections
Aneuploidy, Chr15 IGF-1r loss
PKU
Pancreatic,thyroid
Renal, cong.heart
Cytotoxics,radiation,
rubella,
CMV, mat age extremes

19. Twin growth Discordancy defined as >15% difference
Search for cause of discordancy FGR
abnormality
TTTS
Controversy over twin growth rates
use of singleton charts

21. Alexander et al Clinical Obstet Gynecol 41:1;115-125
50th birthweight percentiles
Alexander et al Clinical Obstet Gynecol 41:1;

22. Placental Localisation
Identify placenta previa
Major previa
Minor previa
Identify succenturiate lobes
Identify vasa previa

23. TA- Sagittal midline suprapubic image

24. Posterior
Placenta Praevia

28. Placental Localisation
When to rescan if identified at:
14 weeks?
20 weeks?
32 weeks?
37 weeks?
Placenta accreta

29. Cervical length Assessment
TA, TL or TV
Indications
Previous cervical surgery
Previous midtrimester losses (14-24 weeks)
Previous PPROM
Previous PTL
Timing
14-18 weeks

32. Cervical length at 18 weeks and risk of preterm delivery  32 weeks
Length(mm)
RR(95%CI)
PPV
(11-76) %
(13-46) %
(11-31) %
(8-21)
(2.4-4)
Hassan et al. Am J Obstet Gynecol 2000; 182:

33. Bulging
membranes