INTRAUTERINE GROWTH RESTRICTION (IUGR)
INTRODUCTION
Intrauterine growth restriction (IUGR) is a term used to describe a condition in which the fetus is smaller than expected for the number of weeks of pregnancy. Another term for IUGR is fetal growth restriction. Newborn babies with IUGR are often described as small for gestational age (SGA)
.
A
fetus with IUGR often has an estimated fetal weight less than the 10th
percentile. This means that the fetus weighs less than 90 percent of all other
fetuses of the same gestational age. A fetus with IUGR also may be born at term
(after 37 weeks of pregnancy) or prematurely (before 37 weeks).
Newborn
babies with IUGR often appear thin, pale, and have loose, dry skin. The
umbilical cord is often thin and dull-looking rather than shiny and fat. Babies
with IUGR sometimes have a wide-eyed look. Some babies do not have this
malnourished appearance but are small all-over.
CAUSES OF IUGR
Intrauterine
growth restriction results when a problem or abnormality prevents cells and
tissues from growing or causes cells to decrease in size. This may occur when
the fetus does not receive the necessary nutrients and oxygen needed for growth
and development of organs and tissues, or because of infection. Although some
babies are small because of genetics most IUGR is due to other causes. Some
factors that may contribute to IUGR include the following:
Maternal factors:
Ø high
blood pressure
Ø chronic
kidney disease
Ø advanced
diabetes
Ø heart
or respiratory disease
Ø malnutrition,
anemia
Ø infection
Ø substance
abuse (alcohol, drugs)
Ø cigarette
smoking
Utero placental factors :
Ø decreased
blood flow in the uterus and placenta
Ø placental
abruption (placenta detaches from the uterus)
Ø placenta
previa (placenta attaches low in the uterus)
Ø infection
in the tissues around the fetus
Fetal factors:
Ø multiple
gestation (twins, triplets, etc.)
Ø infection
Ø birth
defects
Ø chromosomal
abnormality
Ø
COMPLICATIONS OF IUGR
IUGR
can begin at any time in pregnancy. Early-onset IUGR is often due to
chromosomal abnormalities, maternal disease, or severe problems with the
placenta. Late-onset growth restriction (after 32 weeks) is usually related to
other problems.
With
IUGR, the growth of the baby's overall body and organs are limited, and tissue
and organ cells may not grow as large or as numerous. When there is not enough
blood flow through the placenta, the fetus may only receive low amounts of
oxygen. This can cause the fetal heart rate to decrease placing the baby at
great risk.
Babies with IUGR may have problems at birth
including:
Ø decreased
oxygen levels
Ø low
Apgar scores
Ø meconium
aspiration (inhalation of the first stools passed in utero), which can lead to
difficulty breathing
Ø hypoglycemia
Ø difficulty
maintaining normal body temperature
Ø polycythemia
(increased red blood cells)
Severe IUGR may result in stillbirth. It may also
lead to long-term growth problems in babies and children.
Intrapartum Asphyxia
Because
the fetus is compromised with IUGR, its ability to tolerate the stress of labor
is decreased. Therefore, when uterine contractions occur and the flow of blood
to the fetus is diminished with each contraction, the fetus with IUGR may not
be able to adapt. This leads to an imbalance between the ability of the
placenta to supply the fetus with oxygen and nutrients and the need for these
substances. When an imbalance occurs, this may lead to an accumulation of
byproducts resulting in acidosis which can be harmful. If intrapartum asphyxia
is allowed to progress, irreversible brain damage can occur.
Neonatal Hypoglycemia and
Hypocalcemia
As
the result of IUGR, a newborn may be deficient in glucose (sugar) and calcium.
The lack of these important substances can result in significant compromise to
the newborn and result in neurological damage.
Meconium Aspiration
This
occurs when the fetus defecates in the uterus resulting in the appearance of a
brown, murky substance. Meconium aspiration is of major concern. In severe
forms, the newborn may develop lung disease resulting in respiratory and
cardiovascular complications that could lead to neonatal death.
Neurodevelopmental Delay
A
number of studies have shown that fetuses with significant IUGR are at higher
risk for developmental delays, cardiovascular disease, and other problems later
in life. For these reasons, and those stated above, it is important to identify
the fetus with IUGR and manage the pregnancy accordingly
DIAGNOSIS OF IUGR
Fundal Height
The
height of the fundus can be measured from the pubic bone. This measurement in
centimeters usually corresponds with the number of weeks of pregnancy after the
20th week. If the measurement is low for the number of weeks, the
baby may be smaller than expected.
Ultrasound
Ultrasound
is a more accurate method of estimating fetal size. Measurements include the
diameter of the head (Biparietal Diameter or BPD), the circumference of the
head, the circumference of the abdomen, and the length of the femur bone of the
leg. The fetal abdominal circumference is a helpful indicator of fetal
nutrition.
Doppler flow
Another
way to interpret and diagnose IUGR during pregnancy is Doppler flow, which use
sound waves to measure blood flow. The sound of moving blood produces
wave-forms that reflect the speed and amount of the blood as it moves through a
blood vessel. Blood vessels in the fetal brain and the umbilical cord blood
flow can be checked with Doppler flow studies.
Mother's weight gain
A
mother's weight gain can also indicate a baby's size. Small maternal weight
gains in pregnancy may correspond with a small baby.
MANAGEMENT OF IUGR
Management
of IUGR depends on the severity of growth restriction, and how early the
problem began in the pregnancy. Generally, the earlier and more severe the
growth restriction, the greater the risks to the fetus. Careful monitoring of a
fetus with IUGR and ongoing testing may be needed.
Some of the ways to watch for potential problems
include the following:
Ø Fetal
movement counting - keeping track of fetal kicks and movements. A change in the
number or frequency may mean the fetus is under stress.
Ø Non Stress Testing - a test that watches the
fetal heart rate for increases with fetal movements, a sign of fetal well-being.
Ø Biophysical
profile - a test that combines the non stress test with an ultrasound to
evaluate fetal well-being.
Ø Ultrasound
- Ultrasounds are used to view internal organs as they function, and to assess
blood flow through various vessels. Ultrasounds are used to follow fetal
growth.
Ø Doppler
flow studies - a type of ultrasound which use sound waves to measure blood
flow.
TREATMENT OF IUGR
Although
it is not possible to reverse IUGR, some treatments may help slow or minimize
the effects. Management will be determined based on:
Ø Maternal
and fetal overall health, and medical history
Ø the
extent of the condition
Ø tolerance
for specific medications, procedures
Nutrition
Some
studies have shown that increasing maternal nutrition may increase gestational
weight gain and fetal growth.
Bedrest
Bedrest
in the hospital or at home may help improve circulation to the fetus.
Delivery
If
IUGR endangers the health of the fetus, then an early delivery may be
necessary.
PREVENTION
Intrauterine
growth restriction may occur, even when the mother is in good health. However,
some factors may increase the risks of IUGR, such as cigarette smoking and poor
maternal nutrition. Avoiding harmful lifestyles, eating a healthy diet, and
getting prenatal care may help decrease the risks for IUGR. Early detection may
also help with IUGR treatment and outcome. Intra Uterine Growth
Restriction (IUGR)
NURSING DIAGNOSIS
Imbalanced Nutrition,
lessthan bodyrequirementsrelated to prematurity asevidenced byextremely
low birth weight at 10th percentile at birth
Altered
breathing dyspnea related to poor lung maturity secondary to respiratory
distress
Altered
body temperature hypothermia related to immature thermoregulation centre
secondary to less subcutaneous fat.
Altered
nutrition less than body requirement related to poor sucking reflex.
Fluid
volume deficit hypovolumia related to poor intake.
Parental
fear and anxiety related to NICU procedures and child condition
High
risk for complication like hypoglycemia related to poor feeding.
High
risk for infection related to poor immunity.
Parental
knowledge deficit regarding care of low birth weight babies related to lack of
exposure.
Mr.Surasak
Molsrisuk
REFERRENCE
