Small for Gestational Age (SGA)

Small for gestational age (SGA) is a term used to describe babies who are smaller than usual for their gestational age, which is the number of weeks of pregnancy. SGA babies are typically below the 10th percentile in weight for their gestational age.

Causes and Risk Factors

SGA can be caused by a variety of factors, including:

  • Poor maternal nutrition
  • Smoking during pregnancy
  • High blood pressure or preeclampsia
  • Chronic medical conditions, such as kidney disease or heart disease
  • Multiple gestations (carrying twins or other multiples)
  • Placental insufficiency or dysfunction
  • Genetic factors

Diagnosis and Detection

SGA is typically diagnosed during pregnancy through:

  • Ultrasound measurements of fetal size and growth
  • Fundal height measurements (measuring the distance from the top of the pubic bone to the top of the uterus)
  • Estimation of gestational age based on last menstrual period or ultrasound dating

Complications and Risks

Babies born SGA are at increased risk for:

  • Low birth weight
  • Preterm birth
  • Hypoglycemia (low blood sugar)
  • Hypothermia (low body temperature)
  • Respiratory distress syndrome
  • Increased risk of stillbirth
  • Long-term health consequences, such as growth restriction and developmental delays

Management and Treatment

Management of SGA typically involves:

  • Closely monitoring fetal growth and well-being through regular ultrasounds and non-stress tests
  • Controlling underlying medical conditions, such as high blood pressure or diabetes
  • Providing optimal prenatal care and nutrition
  • Considering early delivery if there are concerns about fetal well-being or growth restriction

Prognosis and Outcome

The prognosis for babies born SGA depends on various factors, including:

  • Gestational age at birth
  • Birth weight
  • Presence of underlying medical conditions
  • Quality of prenatal and postnatal care

With proper management and care, many babies born SGA can catch up on their growth and development, and have a normal long-term outcome.

Article last updated on: 15th June 2025.
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