Abnormal Baby Development

Most parents are constantly on the lookout for signs of abnormal development in their children, and worry if their babies do not show certain signs of development when most children do. Babies tend to develop at their own pace, sometimes falling behind in one area or racing ahead in another. As long as development falls within a normal range, reaching a milestone late is usually not a cause for concern. However, if your baby consistently reaches milestones much later than anticipated, you should talk to your doctor.


Babies grow and develop at an incredible speed during their first year of life. If a baby does not reach a milestone at the expected time, she might have a developmental delay in that area. For example, a child normally starts learning to walk between 9 and 15 months. If a 20-month-old child has not started walking, that is a developmental delay.


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Babies develop in several areas, and parents should take notice if their child is having difficulty in a particular one. Developmental areas to look out for include: fine motor skills, including grasping objects; gross motor skills, such as:

  • speaking; self-help skills
  • including feeding oneself;
  • social skills
  • including interacting with others


A clinician uses developmental screening and evaluation tests to identify whether a baby is experiencing abnormal development. Blood tests for newborns screen for genetic, metabolic, hormonal and functional disorders that might affect physical and mental development, according to the March of Dimes. Later in infancy, there are more tests to see if babies are developing normally. Tests can be questionnaires that parents answer or exams performed by a doctor. These tests assess an infant's strengths and weaknesses, and doctors use the results to determine if early intervention is needed.

Risk Factors

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Some babies are susceptible to abnormal development because of genetic or environmental factors. Examples of genetic factors include chromosomal abnormalities that lead to conditions such as Down or Fragile X syndrome, according to Merck Manual Online Medical Library. Environmental risks include exposure to harmful agents before or after birth. Examples include alcohol or drug use by the mother during pregnancy or breastfeeding; diseases such as syphilis or HIV; or poor nutrition during infancy.

Early Intervention

If a parent suspects that his child is developing more slowly than expected, it is important that the child see a clinician for an evaluation assessment. Early intervention can address concerns, identify resources and set a plan of action. Early intervention also helps a baby reach development milestones in multiple areas. For instance, if a child has a speech delay, it might keep her from reaching social or emotional milestones. Focusing on a child’s special needs early can give her the help she needs to keep up with her peers.