What is Prematurity?

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Being premature means having been born early. According to the most currently accepted definition, all children born before 37 weeks of gestation are considered premature.

Types of prematurity

Being born before pregnancy has reached term, means all the organs and systems are less mature, and there is a greater incidence of pathologies that can cause the organs to develop incorrectly.

Logically, the fewer the weeks of gestation the premature baby has had when it is born, the more problems it may suffer. In addition, these are usually more serious and can have more long-term consequences.

There is no universal classification, but that shown below is currently the most widely accepted:

  • Extremely preterm. Born before 28 weeks of gestation. Fortunately, this sub-group only accounts for 1-2% of all live births.
  • Very preterm newborns. Born between weeks 29 and 316 of gestation.

These groups constitute approximately 20% of all premature births. They have the most serious short- and long-term health problems, greater mortality, and require the most financial support, healthcare time, and research resources in neonatology.

  • Moderately preterm. Born between weeks 32 and 346 of gestation.
  • Late preterm. Born between weeks 35 and 366 of gestation.

Substantiated information by:

Marta Arnal
Teresa Cobo
Ana Herranz
Mª Dolors Salvia
Erika Sánchez

Published: 20 February 2018
Updated: 20 February 2018


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