Small for Gestational Age
SGA may be caused by growth problems before birth. This can be due to:
- Lack of nutrients and oxygen to the baby
- A small uterus
- Exposure to certain substances
- Infections or long term illnesses during pregnancy
- Birth defects
- Problems with genes
Sometimes a baby is small because the parents are small. These babies have normal growth. They are just small compared to others their age.
SGA is more common in mothers who have had a prior SGA baby.
During pregnancy, problems in the mother can raise the risk. They include:
- High blood pressure
- Smoking, using street drugs or drinking alcohol
- Problems with the placenta, such as placental abruption or placenta previa
- Poor nutrition and not taking folic acid
- Long term medical problems, such as kidney failure , gestational diabetes , asthma , systemic lupus erythematosus , celiac disease , or anemia
- Certain infections
- Taking certain medicines
Other things that raise the risk are:
- Pregnancy with more than one fetus—such as twins or triplets
- Birth defects or genetic problems in the baby
A baby with SGA is often diagnosed before birth. A physical exam will be done on the mother. Measurements will be taken of the mother’s belly, weight, and uterus (womb). They are based on the number of weeks of pregnancy. If the measurements are low, the baby may be smaller than average. SGA may also be diagnosed at birth based on the baby’s weight and height.
Images may be taken during pregnancy with an ultrasound.
The goal is to watch for and treat problems in the mother and baby.
Babies that have SGA from lack of nutrition or oxygen may need treatment. Options are:
The doctor may:
- Monitor the baby’s growth
- Deliver the baby early— if growth problems are severe
- Treat health problems in the mother
Babies who are born with SGA may be weak. They may not be able to feed enough or stay warm. Treatment may include:
- Using warming beds or incubators
- Tube feedings
- Checking oxygen levels
Monitoring and treatment may also be needed during childhood.
This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.
Edits to original content made by Denver Health.
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American Pregnancy Association http://americanpregnancy.org
Healthy Children—American Academy of Pediatrics http://www.healthychildren.org
Canadian Paediatric Society http://www.cps.ca
Health Canada https://www.canada.ca
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