How Common Are Birth Defects?

According to data gathered from the Centers for Disease Control, cerebral palsy (CP) is the most common motor disability in childhood with international population-based studies suggesting estimates of CP ranging from 1.5 to more than 4 per 1,000 live births. About 1 in 323 children has been identified with CP according to estimates from (ADDM) Network.

In 2008 (most recent data compiled), the CDC’s Autism and Developmental Disabilities Monitoring (ADDM) CP Network included areas of Alabama, Georgia, Missouri, and Wisconsin. Based on children who were 8 years old and living in these four communities in 2008, the ADDM CP data showed that:

  • CP was more common among boys than among girls.
  • CP was more common among Black children than White children. Hispanic and White children were about equally likely to have CP.
  • Most (77.4%) of the children identified with CP had spastic CP.
  • Over half (58.2%) of the children identified with CP could walk independently.
  • Many of the children with CP also had at least one co-occurring condition—41% had co-occurring epilepsy and 6.9% had co-occurring ASD.

Walking Ability

According to 2006 data from the ADDM CP Network, Black children with cerebral palsy were 1.7 times more likely to have limited or no walking ability compared with White children. Overall findings included:

  • 41% of children with CP were limited in their ability to crawl, walk, run, or play
  • 31% needed to use special equipment such as walkers or wheelchairs.
  • 58.2% of children with CP could walk independently
  • 11.3% walked using a hand-held mobility device
  • 30.6% had limited or no walking ability

Evidence of Co-Occurring Developmental Disabilities

  • Almost half (41%) of the children identified with CP by the ADDM CP Network had co-occurring epilepsy. Co-occurring epilepsy frequency was highest among children with cerebral palsy who had limited or no walking ability.
  • Some (6.9%) of the children identified with CP also had autism spectrum disorder (ASD). Co-occurring ASD frequency was higher among children with non-spastic CP, particularly hypotonic CP.

Non-Spastic CP – a form of CP marked by weakened and unstable muscle tone

Some signs include:

  • Sudden, jerky movements
  • Variations of muscle tone, ranging from stiff to loose.

Hypotonic CP – marked by extremely loose and floppy muscle tone

Some signs include:

  • Rag-doll appearance due to limp muscles
  • The head may fall backwards, forward, or to each side involuntarily
  • Respiratory problems
  • Difficulty maintaining proper posture

Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP) in Atlanta shows for 2008 that:

  • Approximately 60% of 8-year-old children with CP had another developmental disability
  • More than 40% of children with CP had intellectual disability
  • 35% had epilepsy
  • Greater than 15% had vision impairment
  • Nearly 25% of children with CP had both intellectual disability and epilepsy.

Risk Factors

  • Low birth weight
  • Premature birth
  • Disruption of blood and oxygen supply to the brain
  • Infections in the mother
  • Being born a twin or other multiple birth
  • Being conceived by in vitro fertilization or other assisted reproductive technology
  • Having a mother who had an infection during pregnancy
  • Having kernicterus (a type of brain damage that can happen when severe newborn jaundice goes untreated)
  • Having complications during birth

Early Signs of Cerebral Palsy

From birth to 5 years of age, a child should reach movement goals―also known as milestones―such as rolling over, sitting up, standing, and walking. A delay in reaching these movement milestones could be a sign of CP. The following are some other signs of possible CP.

In a baby 3 to 6 months of age:

  • Head falls back when picked up while lying on back
  • Seems to overextend back and neck when cradled in someone’s arms
  • Legs get stiff and cross or scissor when picked up
  • Feels stiff
  • Feels floppy

In a baby older than 6 months of age:

  • Has difficulty bringing hands to mouth
  • Reaches out with only one hand while keeping the other fisted
  • Doesn’t roll over in either direction
  • Cannot bring hands together

In a baby older than 10 months of age:

  • Crawls in a lopsided manner, pushing off with one hand and leg while dragging the opposite hand and leg
  • Scoots around on buttocks or hops on knees, but does not crawl on all fours