Late preterm infants – impact of perinatal factors on neonatal results. A clinical study
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I Department of Obstetrics and Gynecology, Medical Centre of Postgraduate Education, Warsaw, Poland
Department of Neonatology, Medical Centre of Postgraduate Education, Warsaw, Poland
Ann Agric Environ Med 2015;22(3):536–541
Infants born between the 34th – 36th week of pregnancy account for 75% of all preterm infants. Their seemingly slight immaturity is related to serious health problems.

The aim of the study was to analyse perinatal factors that influence the occurrence in infants of such problems as respiratory failure, metabolic problems and early onset sepsis (EOS).

Material and Methods:
The material for the study included all mothers and their late preterm infants: 34+0 – 36+6 born in our hospital (a tertiary referral academic centre) in 2010 and 2011. The course of pregnancy and delivery, the type of delivery, applied preventive measures and treatment, as well as demographic data and the clinical state of infants were all analysed. Data from individual documentation of each mother and infant were collected by 5 designated people and data reliability was independently monitored by a random control of the documentation conducted by the supervising person.

A statistically significant relationship between the occurrence of respiratory distress syndrome and infant immaturity, bad state after birth and sepsis in infants were confirmed. Sepsis was more common in the case of vaginal delivery, and coexisted with respiratory distress syndrome. The mother’s diseases during pregnancy, a perinatal preventive antibiotic therapy, and possible delivery complications did not influence the infection. Perinatal asphyxia in an infant positively correlated with a Caesarean section and respiratory distress syndrome after birth.

It is necessary to thoroughly establish the type of delivery of a late preterm infant in order to prevent an infection in the newborn child. The improvement of diagnosis of intrauterine hypoxia may reduce the number of Caesarean sections. The decision about late preterm delivery should be based on indices of the mother’s state of health. Premature delivery is related to the occurrence of respiratory distress syndrome in a late preterm infant, although the risk is reduced by the application of an antenatal steroid therapy.

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