Intrauterine Growth Restrictions Flashcards
What is intrauterine Growth Restriction?
It is the failure of the fetus to meet its growth potential. Undetected fetal growth restrictions is the leading cause of STILL BIRTHS, they are more likely to suffer neurocognitive defects, long term health problems in childhood and adult life. Detection allows intervention in the antenatal period.
What does small for weight (SFW) mean?
it means birth weight less than the 10th centile
What is the clinical significance of IUGR? What are the implications on the fetus?
- There increased chance of preterm labour
- Increased Perinatal mortality: increased still births and increased Neonatal deaths
- Neonatal morbidity increases: Hypothermia, infection, Hypoglycaemia
Irritable and poor feeders
Meconium aspiration, HIE (Hypoxic ischaemic encephalopathy)
What is the clinical significance of IUGR long term?
- Motor and intellectual Handicap (increased chances of cerebral palsy and mental retardation)
- Adult morbidity and mortality, developmental origins of adult disease
What is the developmental origins of adult disease (DOAD)? Explain this hypothesis
- This is that birthweight is inversely related to the risk of :
- Hypertension
- Diabetes
- Dyslipidaemia
- Vascular diseases associated with the above
List fetal aetiology of IUGR?
- Congenital
- Infections
- Multiple pregnancy
List maternal aetiology/ risk factors of iUGR?
- Vascular disease, thrombophilia (hypercoagulability), toxins
- Malnutrition
- Medical Disease: Pre-pregnancy diabetes, renal disease, SLE, hyperthyroidism, cardiac disease, hypertension, antiphospholipid syndrome
- Cardiac disease, anaemia, Atmospheric - Respiratory hypoxia
- Pre-eclampsia
- Previous FGR baby
- Uterine structural anomalies
Social factors: Smoking, alcohol, cocaine
List placental aetiology of IUGR?
- Multiple pregnancies
- Placental abruption
- Placental abnormalities
✚ Low PAPP-A or β-hCG in first trimester
✚ High second trimester alpha-fetoprotein
✚ High-resistance uterine artery Doppler in second trimester
List and describe in greater detail the congenital aetiology of IUGR?
- Chromosomal: Trisomy 21, Trisomy 18, Trisomy 13, Turners syndrome XO (has a high miscarriage rate)
- Single gene disorders
- Structural Defects: Gastrochisis (defect in anterior abdominal wall through which contents readily pass through), Omphalocoele (intestines and organs remain outside the gastric sac), Diapragmatic hernia, skeletal dysplasia, CHD
- Infection: TORCH - Toxoplasmosis (uncooked meats, cats, soil), Other, Rubella, Cytomegalovirus (obtained from carrier, always wash hands), Herpes simplex virus, HIV
What is involved in a thrombophilia screen?
- Antiphospholipid syndrome
- Antithrombin III
- Protein C
- Protein S
- Factor 5 Leiden
- Hyperhomocystanaemia
(How do we screen for IUGR? What is the most effective method or gold standard?
Check symphaseal fundal height (detects about 2/3 of SFD’s)
- Intraobserver reliability > interobserver reliability, continuity of care is important
Ultrasound
- More effective than SFH
- Optimal timing is approximately 34 weeks
- Optimal single biometric measure = AC
Prevention of IUGR?
- Aspirin
- Work and rest optimisation
- interventions aimed at preventing aneuploidy (early diagnosis)
How do you check if the fetus is genetically small, and not due to other adverse effects?
The fetus is genetically small
- Parental small stature
- Absence of recognised risk factors
- Symmetrically small
- Normal growth trajectory
- Biophysically active
- Normal amniotic fluid
- Normal umbilical and other Doppler studies
What two forms of investigations are carried out for fetal surveillance?
- Cardiotocography
- Ultrasound
What is low birth weight?
< 2500 g
What is very low birth weight?
<1500 g
Name the risk factors for fetal growth restriction?
hypertension, preeclampsia, diabetes, smoking, obesity and advanced maternal age.
Ultrasound is the mainstay in terms of assessment of the small fetus, what parameters are measured?
fetal size and weight
▪ blood flow in the umbilical artery (umbilical artery Doppler assessments) and Doppler assessments of fetal circulation, where indicated
▪ parameters of fetal wellbeing (amniotic fluid volume and biophysical profile).
What is late onset FGR detected in the third trimester generally caused by?
Uteroplacental insufficiency
What is early onset FGR in the first trimester generally caused by?
Generally occurs due to a fetal problem
- It could be do to UPI, UPI describes
UPI describes the group of pregnancies where growth is poor due to poor nutrient and oxygen supply to the fetus, because of inadequate placental function
If FGR is detected late second or early third trimester or is very severe other investigations may be required
- Maternal history should be taken
- Earlier investigations and assessments should be reviewed
- Maternal Serology for CMV, rubella and syphilis
- High level ultrasound for structural anomalies
- Amniocentesis for karaotype
what are some management strategies to improve fetal growth?
- L-arginine
- Sildenafil
- Hyper alimentation
- Aspirin
- LMWH
- BEd rest
When is delivery of the fetus indicated in IUGR?
- Depending on the gestation and severity of FGR and any coexisting complications such as pre-eclampsia, delivery may be indicated by one or more of abnormal CTG, abnormal fetal Doppler, low AFI or mother reporting reduced fetal movements.
Timing of delivery, what is the most optimum?
37-38 weeks, induction of labour here does not increase C Section rates, and has a lower risk of still birth.
Amniotic fluid index? What does it mean?
a sum of the maximum vertical pocket (MVP) measured in each of the four quadrants of the uterus ( Fig 11.7 ). A compromised fetus will divert well-oxygenated blood from the kidneys in order to adequately perfuse more important organs, including the brain, heart and adrenals. Less renal blood supply leads to less urine output and so less amniotic fluid. Caution must always be taken with interpreting a finding of reduced AFI that it does not represent ruptured membranes (common) or fetal urinary tract pathology
Assessment of fetal Biophysical profile, what does it involve?
Another modality involved in addition to the CTG and ultrasound. The BPP consists of the ultrasound assessment of fetal movement, breathing tone, AFI, and CTG
