Babies born just a few weeks prematurely are more than three times as likely to have cerebral palsy than full-term infants. In fact, those last few weeks of pregnancy are critical to a child’s health and development.

New research indicates that late preterm infants (those born 34-36 weeks gestation) had a much higher risk of developmental delays than babies born full-term.

The earlier an infant is born, the higher the risk of some neuro-developmental problems, the research shows. For example, infants born between 30 and 33 weeks gestation were nearly eight times as likely as full-term infants to have cerebral palsy. This adds to the growing body of evidence showing that being born just a few weeks too soon can have lasting consequences that can no longer be described as temporary or benign. These findings reinforce the message that a few extra weeks of pregnancy can have a beneficial effect to an infant’s health.

Late preterm babies account for more than 70 percent of all preterm births and for the majority of the increase in preterm birth rates during the past two decades. Late preterm infants have a greater risk of birth defects, breathing problems, feeding difficulties, temperature instability (hypothermia), jaundice, delayed brain development and death than babies born at term. This new analysis shows that these late preterm infants also have three times the risk of cerebral palsy and a slightly higher risk of mental retardation.

Exactly what causes the increased risk of birth defects like cerebral palsy and neuro-developmental delays in late preterm infants should be the subject of future research. However, there are several theories, including risk factors during the pregnancy that may contribute to damage in utero, or complications related to the preterm birth.