Late preterm births: an "almost" overlooked group of newborns

Maria Elisabeth Lopes Moreira

Every year, four million babies die in the first 28 days of life. This equates to more than 10,000 deaths per day worldwide, most of which are related to premature childbirth. In 2000, at the Millennium Summit of the United Nations, the World Health Organization established and signed a pact with 191 countries containing eight millennium development goals. The fourth of these goals was the pledge to reduce the mortality rate of children under five years of age by two thirds by 2015.

In Brazil, the infant mortality rate was 14/1000 live births in 2011. The country has already achieved the millennium development target with respect to the fourth goal. However, neonatal mortality has not seen a similar reduction and the rates of preterm births increased slightly.

The causes for the increase in preterm birth are not well defined, but several epidemiologists attribute it to induced birth by caesarean section or induction of delivery. Despite saving the lives of mothers and babies, cesareans are being used in an abusive clinical manner. In Brazil, all one need do is look at the number of cesareans scheduled on dates considered to be cabalistic (10/10/2010, 11/11/2011, 12/12/2012) in private hospitals, plus excess scheduling prior to public holidays, especially before long holiday weekends.

The increased number of these cesarean deliveries programmed before 40 weeks, which is the expected and desired duration of a pregnancy, is a worldwide phenomenon and has led to the occurrence of late preterm births in the neonatal area.

"Late Preterm" is the name given to newborns delivered at a gestational age of between 34 and 36 weeks. This terminology to describe newborns previously called "close to term," has changed recently, because the way of classifying it previously gave the impression that it was almost a normal occurrence. The expression "near term" gave a false sense of security to those dealing with the interruption of gestation. The six remaining weeks to complete the total of 40, for example, are indeed a critical period for development of the brain and lungs. Anticipation of birth of this kind can have significant repercussions on the health of the newborn child.

Increased morbidity in newborns called "before term," namely those born after 37 but before 39 weeks, is also in current use. These infants born at 37 to 38 weeks of gestation are more likely to suffer a series of undesirable complications, such as the need for resuscitation, hospitalization and consequent separation from the mother due to hypoglycemia, hypothermia, respiratory difficulties, jaundice and feeding difficulties. Such problems may lead to early weaning, re-hospitalization and cognitive changes, which at school age can impair learning, among others.

In Brazil, research and resources have been directed in recent years to newborns under 32 weeks weighing less than 1500g, with programs to monitor these infants at risk. The same has not occurred in relation to the impact of premature delivery on the health of the late preterm infant, which has been largely ignored, and without early detection of problems related to their development. Various authors have recommended that these newborns should participate in monitoring programs for newborns at risk for no less than 18 months.

Admittedly, the majority of late preterm births (approximately 80%) will have a neonatal delivery without any complications. However, when compared with those born at between 39 and 41 weeks, the chances of suffering some type of morbidity in the short and long term has already been proven to be greater. The closer gestational age advances towards the full 40 weeks, the more the health risks diminish, although they are still present in newborns of 37 to 38 weeks.

Avoiding interruption of pregnancy at a stage of gestation at which the newborn is not fully developed can make a marked difference in the health of babies.

Publication Dates

  • Publication in this collection
    July 2014
ABRASCO - Associação Brasileira de Saúde Coletiva Rio de Janeiro - RJ - Brazil