What is Microcephaly?

What Is Microcephaly?

Microcephaly is a birth defect that results in a baby’s head being smaller compared to other babies of the same gender and age. In addition, babies with it have smaller brains and may not have developed properly during pregnancy or has stopped developing after birth. State birth defects tracking systems have estimated that microcephaly ranges from 2 babies per 10,000 live births to about 12 babies per 10,000 live births in the Unites States.1


Babies with microcephaly can have a range of other problems, depending on how severe it is and can range from mile to severe and are often lifelong and life threatening. Some of those problems include:

  • Seizures
  • Developmental delay, such as problems with speech or other developmental milestones (like sitting, standing, and walking)
  • Intellectual disability (decreased ability to learn and function in daily life)
  • Problems with movement and balance
  • Feeding problems, such as difficulty swallowing
  • Hearing loss
  • Vision problems

Causes and Risk Factors

Unfortunately, the causes of microcephaly in most babies are unknown. Some babies have it because of changes in their genetics. and others can include the following exposures during pregnancy:

  • Certain infections during pregnancy, such as rubellatoxoplasmosis, or cytomegalovirus
  • Severe malnutrition, meaning a lack of nutrients or not getting enough food
  • Exposure to harmful substances, such as alcohol, certain drugs, or toxic chemicals
  • Interruption of the blood supply to the baby’s brain during development

Some babies developed the birth defect because their mothers contracted the Zika virus while pregnant. Researchers are studying the possible link between Zika virus infection and microcephaly. Zika is spread mostly by the bite of an infected Aedes species mosquito (Ae. aegypti and Ae. albopictus). These mosquitoes are aggressive daytime biters. They can also bite at night. You should try to avoid mosquitos and remove standing water from around your home. You may even consider getting a pest control company to spray your home to reduce the mosquito population.