NORMAL FOETAL GROWTH
• Cellular hyperplasia
• Hyperplasia and hypertrophy
• Stage I (Hyperplasia)
- 4 to 20 weeks
- Rapid mitosis
- Increase of DNA content
• Stage II (Hyperplasia & Hypertrophy)
- 20 to 28 weeks
- Declining mitosis.
- Increase in cell size.
• Stage III ( Hypertrophy)
- 28 to 40 weeks
- Rapid increase in cell size.
- Rapid accumulation of fat, muscle and
• 95% of fetal weight gain occurs during last
20 weeks of gestations.
Small stature/ low pre-pregnancy weight
• A Chromosome Defect In second trimester 20% SGA fetuses have
Triploid is most common under 26 wks.
Trisomy-18 is common after 26 wks .
Other are 21(Down’s syndrome), 16, 13, xo
• Exposure to an infection• German measles (rubella),
cytomegalovirus, herpes simplex,
tuberculosis, syphilis, or toxoplasmosis,
TB, Malaria, Parvo virus
• birth defects
• (cardiovascular, renal, anencephally, limb
• A primary disorder of bone or cartilage.
• A chronic lack of oxygen during
• Placenta or umbilical cord defects.
• Uteroplacental Insufficiency
Resulting From -.
– Improper / inadequate trophoblastic
invasion and placentation in the first
– Lateral insertion of placenta.
– Reduced maternal blood flow to the
• Fetoplacetal Insufficiency Due To-.
– Vascular anomalies of placenta and
– Decreased placental functioning mass-.
• Small placenta, abruptio placenta,
placenta previa, post term pregnancy
Environmental Causes of IUGR
• High altitude - lower environmental oxygen
Types of IUGR
• Symmetric IUGR:
(33 % of IUGR Infants)
• Asymmetric IUGR
(55 % of IUGR)
• Combined type IUGR:
(12 % of IUGR)
• height, weight, head circ proportional
• early pregnancy insult:
• commonly due to congenital infection,
genetic disorder, or intrinsic factors
• Reduced no of cells in fetus
• normal ponderal index
• low risk of perinatal asphyxia
• low risk of hypoglycemia
• The ponderal index is used determine
those infants whose soft tissue mass is
below normal for their stage of skeletal
Ponderal Index =
birth weight x 100
• Typical values are 20 to 25.
• Those who have a ponderal index below
the 10th % can be classified as SGA
• PI is normal in symmetric IUGR.
• PI is low in asymmetric IUGR
• later in pregnancy:
• commonly due to utero placental
insufficiency, maternal malnutrition,
hypoxia, or extrinsic factors
• low ponderal index
• Cell number remains same but size is
• increased risk of asphyxia
• increased risk of hypoglycemia
• Growth restriction in the stage of
• Brain sparing effect
• Head growth remains normal but
abdominal girth slows down
Newer Classification: 1. Normal Small Fetuses-
Have no structural abnormality,
normal umbilical artery & liquor but
wt., is less.
They are not at risk and do not need any
Abnormal Small Fetuses- have
chromosomal anomalies or structural
malformations. They are lost cases and
deserve termination as nothing can be
Growth Restricted Fetuses- are due to
impaired placental function. Appropriate &
timely treatment or termination can
• Signs of recent wasting
- soft tissue wasting
- diminished skin fold thickness
- decrease breast tissue
- reduced thigh circumference
• Signs of long term growth failure
- Widened skull sutures, large
- shortened crown – heel length
- delayed development of epiphyses
PREDICTION OF IUGR
last menstrual period - most precise
size of uterus
time of quickening (detection of
• Examination /
• more for gestation in the absence of fetal
anomaly, there is a 5-10 fold increase in
the risk of FGR
• Uterine Artery Doppler Velocimetry
- Notching of the waveform /reduce
associated 3-fold increase in risk of
• Bright or echogenic fetal bowel in the
second trimester is associated with
increase risk of FGR.
• Combination of un-explain elevated
maternal AFP is powerful predictor of
adverse perinatal outcome (FGR)
• Increase AFP combine with echogenic
bowel is strong predictor of FGR
• DOPPLER OF THE UMBILICAL ARTERY
• Reduced end diastolic flow.
Absent end diastolic flow
Reversed end diastolic flow( severe
- Perinatal asphyxia
- Persistent pulmonary hypertension
- meconium aspiration
- Hypothermia due to diminished
subcutaneous fat and elevated
- result from inadequate glycogen
- diminished gluconeogenesis.
- increased BMR
- due to high serum glucagon level,
which stimulate calcitonin excretion
- hyperviscosity and polycythemia due to
increase erythropoietin level sec. to
- IUGR have increased protein catabolism
and decreased in protein, prealbumin and
immunoglobulins, which decreased
humoral and cellular immunity.
• Fetal distress,
• Hypoxia, Acidosis and Low Apgar Score
Increased perinatal morbidity and mortality
Grade 3-4 intraventricular haemorrhage
Brfore 32 wks
more than 1
FL:AC IS 22at all gest wks from 21 wks to
• More than 23.5 indicate IUGR