Small for gestational age is used to refer to a baby who is smaller than the usual size  for the number of weeks of pregnancy. These babies usually have the birth weights below the 10th percentile for babies of the same gestational  age. They may appear physically and neurologically mature  but are smaller than other babies of the same gestational age. SGA babies may be proportionately small (equally small all over) or they may be of normal length and size but have lower weight and body mass. This condition can occur in babies who are premature, full term or post term.

What causes SGA ?

Some babies are small because of genetics . However babies with SGA are small because of fetal growth problems that occur during pregnancy. Many babies with SGA have Intrauterine Growth Restriction IUGR which occurs when the fetus does not receive the necessary nutrients and oxygen needed for proper growth and development of organs and tissues. IUGR is often due to

• chromosomal abnormalities
• maternal disease
• serious placental problems

Some other factors that may contribute to SGA and/or IUGR are :

Maternal Factors 

• High blood pressure
• Chronic Kidney disease
• Advanced diabetes
• Malnutrition
• Anemia
• Heart or respiratory disease
• Infection
• Substance use ( alcohol, drugs)
• Cigarette smoking

Factors involving the uterus and placenta

• Decreased blood flow in the uterus and placenta
• Placenta previa
• Placental abruption
• Infection in the tissue around the fetus

Factors related to developing fetus

• Multiple  pregnancy  ( for example twins, triplet)
• Infection
• Birth defects
• Chromosomal abnormalities

Why should i be concerned ?

Babies with this condition can  have  problems at birth including the following :

• Decreased oxygen levels
• Low APGAR scores
• Meconium aspiration
• Hypoglycemia ( low blood sugar)
• Difficulty maintaining normal body temperature
• Polycythemia (too many red blood cells)

What is the treatment for babies with SGA ?

Treatment depends on the following :

• Your baby’s gestational age , overall health  and medical history
• Severity of the condition
• The baby’s tolerance for specific medications, procedures or therapies
• Expectations of the course of the condition
• Your opinion or preference

These babies may be physically mature than their small size indicates. However they may be weak and less able to tolerate large feedings or to stay warm. Treatment include :

• Temperature controlled beds or incubators
• Tube feedings (if the baby does not have a strong suck)
• Checking for hypoglycemia (low blood sugar) through blood tests
• Monitoring of oxygen levels

Babies with this condition who are also premature may have additional needs including oxygen and mechanical help to breathe.

NOTE

It is important to do the following during pregnancy to reduce your risk of this condition

• Go for prenatal checkups
• Don’t  smoke or abuse substances such as drugs and alcohol
• Eat healthy