Max MongelliWomen & Childrens’ Health
Nepean HospitalSydney, Australia
Assessment and Management of Abnormal Fetal Growth
Updated December 2009
Max Mongelli 2009
Max Mongelli 2009
Fields to be covered:Fields to be covered:
� Prevention
� Screening
� Diagnosis
� Management
� Long term complications
Max Mongelli 2009
Prevention of IUGRPrevention of IUGR
� Stop smoking� Avoid D & A� Aspirin if indicated� Minimize risk of multiple pregnancy� Minimize risk of infections� Treat thrombophilias� Pre-conceptional counselling
Max Mongelli 2009
NotNot effective in prevention:effective in prevention:
� Bed rest� Antihypertensive therapy� Folic acid� Long-chain PU fatty acids� Beta-mimetics
Max Mongelli 2009
Prevention of Prevention of MacrosomiaMacrosomia
� Normalise BMI prior to conception
� Early detection of GDM
� Good control of GDM
� ? Moderate exercise during pregnancy
Max Mongelli 2009
Screening for Abnormal Screening for Abnormal FetalFetal GrowthGrowth
� Fetal size estimation by palpation alone can be inaccurate
� Better results by measuring the symphysis-fundus height (SFH)
Max Mongelli 2009
Technique of SFH Technique of SFH MeasurementMeasurement
� Patient supine, bladder empty.
� Measuring tape should be blank on one side, cm markings on other side. Blank side up.
� SFH measured in cm from top of uterine fundus to the top of symphysis pubis.
� Measurement plotted on reference chart.
Max Mongelli 2009
Reference Charts for Antenatal Reference Charts for Antenatal Screening for Abnormal Screening for Abnormal FetalFetal GrowthGrowth
� Unadjusted, population based charts: inaccurate for many women
� Individually adjusted charts: customised growth charts
� Customised charts have lower false positive rates than unadjusted charts.
Max Mongelli 2009
Reference Charts for Antenatal Reference Charts for Antenatal Screening for Abnormal Screening for Abnormal FetalFetal GrowthGrowth
� Unadjusted, population based charts: inaccurate for many women
� Individually adjusted charts: customised growth charts� Customised charts have lower false positive rates than
unadjusted charts.� Better correlation with perinatal outcomes
Max Mongelli 2009
Examples of Customized Growth Examples of Customized Growth Charts for Antenatal Screening Charts for Antenatal Screening
Max Mongelli 2009
xX
Max Mongelli 2009
Max Mongelli 2009
Max Mongelli 2009
Max Mongelli 2009
Antenatal Diagnosis of Antenatal Diagnosis of SGA/IUGRSGA/IUGR
� SFH measurements alone cannot confirm.
� Possibility of IUGR if there is a growth deceleration pattern or a single small SFH measurement.
� Ultrasound examination is indicated if there is clinical suspicion.
Max Mongelli 2009
Max Mongelli 2009
Ultrasound Diagnosis of Ultrasound Diagnosis of SGA/IUGRSGA/IUGR
� Fetal biometry: HC, BPD, FAC, FL
� Can be converted to an estimated fetalweight (EFW)
� Amniotic fluid index (AFI)
� Doppler studies of umbilical arteries
� Screen for fetal anomalies (10% of IUGR)
� Cardiotocography (non-stress test)
Max Mongelli 2009
KaryotypeKaryotype
Fetal karyotype may be indicated if:
� IUGR is of early onset
� Severe (< 3rd pct)
� Associated with polyhydramnios
� Structural anomalies are present
Max Mongelli 2009
Doppler StudiesDoppler Studies
� Examination of umbilical arteries and MCA
� Proven to reduce PNM by 30%
� Abnormal if absent or reversed diastolic flow
� If abnormal in ductus venosus, fetal risk is very high
Max Mongelli 2009
Management of IUGR:Management of IUGR:InvestigationsInvestigations
� FBC, EUC, LFT’s, urate
� LAC, antiphospholipid antibodies
� TORCH/viral studies
� Chromosome studies
� Tests for celiac disease if indicated
Max Mongelli 2009
Management of IUGR:Management of IUGR:Conservative or elective Conservative or elective
delivery?delivery?
� Depends on severity of IUGR
� If close to term and fetus not compromised, induction of labour
� If there are signs of fetal distress cesarean section is indicated.
Max Mongelli 2009
Management of IUGR:Management of IUGR:ConservativeConservative
� Twice weekly U/S for AFI/flows
� Daily CTG’s
� 2 -weekly EFW measurements
� Antenatal steroids
� Pregnancy should not extend beyond 40 weeks’ gestation
Max Mongelli 2009
Complications of IUGR:Complications of IUGR:Short termShort term
� Hypoglycemia
� Hypothermia
� Hyperviscosity syndrome
� Impaired immune function
� RDS / NEC if preterm
� Birth asphyxia
Max Mongelli 2009
Complications of IUGR:Complications of IUGR:long termlong term
� Cerebral palsy
� Small decrease in IQ
� Reduced scores for executive cognitive functions
� Risk related to severity of IUGR
Max Mongelli 2009
The Barker HypothesisThe Barker Hypothesis
� IUGR fetuses compensate for adverse intrauterine environment by endocrine-metabolic reprogramming
� In adult life this leads to increased risk of hypertension, hypercholesterolemia, IGT, IHD
Max Mongelli 2009
Management of Management of MacrosomiaMacrosomia
Max Mongelli 2009
Differential Diagnosis of Differential Diagnosis of High SFHHigh SFH
� Macrosomia
� Polyhydramnios
� Multiple pregnancy
� Uterine fibroids
� Pelvic masses
� Maternal obesity
Max Mongelli 2009
Diagnosis of Diagnosis of LGA/LGA/MacrosomiaMacrosomia
� Ultrasound biometry
� Conversion to an estimated fetal weight
� Some centres use FAC only
� Cut-off for LGA is EFW>90th pct
� Cut-off for macrosomia 4500 g or 5000 g
Max Mongelli 2009
Accuracy of UltrasoundAccuracy of Ultrasound
� Less accurate for big babies
� Sensitivity ranges from 22% to 69%
� May not be more accurate than clinical palpation alone
Max Mongelli 2009
Complications of Complications of MacrosomiaMacrosomia
� Birth trauma
� Shoulder dystocia
� Erbs’ Palsy
� Birth asphyxia
� Neonatal hypoglycemia
� Neonatal jaundice
� Hypercalcemia, hypomagnesemia
Max Mongelli 2009
Shoulder Shoulder dystociadystocia
� Variable incidence – 0.5%
� Difficult to predict – recurrence risk 10%
� More likely in macrosomia, GDM, post-term, instrumental delivery, prolonged second stage
� 50% have no risk factors
Max Mongelli 2009
Complications of Complications of MacrosomiaMacrosomia::Long TermLong Term
� In GDM offspring
� Neurodevelopmental delay
� Reduced head circumference at 3 years of age
� Greater risk of type 2 DM
� Obesity
Max Mongelli 2009
Management of Management of MacrosomiaMacrosomia::Vaginal Delivery or C/S ?Vaginal Delivery or C/S ?
� Controversial issue
� Shoulder dystocia difficult to predict
� Some centres use 4500 g or 5000 g
� RCOG does not recommend C/S for suspected macrosomia
Max Mongelli 2009
Management of Management of MacrosomiaMacrosomia::Induction of Induction of LaborLabor ??
� Common request from patients
� No evidence that it reduces the risk of shoulder dystocia
� May possibly increase the risk of shoulder dystocia
Max Mongelli 2009
Postnatal Management of Postnatal Management of Unexpected/Undiagnosed IUGRUnexpected/Undiagnosed IUGR
� Many cases of IUGR not diagnosed until after delivery
� Confirmation with customised birth weight percentile
� Maternal follow in clinic to exclude underlying medical conditions
