Late preterms: are they all the same?

Analysis of cases of premature rupture of membranes and preterm births to identify effective management measures to prevent them

OBJECTIVE

Aim: Based on retrospective analysis recognize the key factors of development of premature childbirth and elaborate highly specific criteria for individual prognosis to improve perinatal outcomes.

PATIENTS AND METHODS

Materials and Methods: A retrospective analysis of the birth histories of 250 women and their newborns with spontaneous preterm births at 22-36 weeks was conducted using archival data from the department for pregnant women with obstetric pathology of the State Institution "Institute of Pediatrics, Obstetrics and Gynecology named by academician OM Lukianova of the National Academy of Medical Sciences of Ukraine".

RESULTS

Results: Important risk factors for premature rupture of membranes (PROM) in preterm pregnancy include the presence of sexually transmitted diseases (χ2=31.188, p=0.001), bacterial vaginosis (χ2=30.913, p=0.0001), a history of abortion and/or preterm birth (χ2=16.62, p=0.0002), SARS during pregnancy (χ2=16.444, p=0.0002), chronic adnexitis in anamnesis (χ2=11.522, p=0.0031), inflammatory cervical disease (χ2=11.437, p=0.0032), anaemia (χ2=10.815, p=0.0044), isthmic-cervical insufficiency (ІСІ) (χ2=10.345, p=0.0057), chronic pyelonephritis with exacerbation (χ2=9.16, p=0.01), smoking during pregnancy (χ2=10.815, p=0.0044).

CONCLUSION

Conclusions: The results of a retrospective analysis of 250 cases of preterm birth at 22 to 36 weeks allowed us to identify ways to effectively use existing diagnostic measures to determine readiness for pregnancy and the possibility of prolonging pregnancy to the viability of the newborn. Ways to improve the prevention of preterm birth and the design of further research were identified.

Late preterm: a new high risk group in neonatology

Late preterm infants are those infants born between 34 0/7 weeks through 36 6/7 week of gestation. These are physiologically less mature and have limited compensatory responses to the extrauterine environment compared with term infants. Despite their increased risk for morbidity and mortality, late preterm newborns are often cared in the well-baby nurseries of hospital after birth and are discharged from the hospital by 2-3 days of postnatal age. They are usually treated like developmentally mature term infants because many of them are of same birth weight and same size as term infants. There is a steady increase in the late preterm birth rate in last decade because of either maternal, fetal, or placental/uterine causes. There has been shift in the distribution of births from term and post-term toward earlier gestations. Although late preterm infants are the largest subgroup of preterm infants, there has been little research on this group until recently. This is mainly because of labeling them as "near-term". Such infants were being looked upon as "almost mature", and were thought as neonate requiring either no or minimal concern. In the obstetric and pediatric practice, late preterm infants are often considered functionally and developmentally mature and often managed by protocols developed for full-term infants. Thus, limited efforts are taken to prolong pregnancy in cases of preterm labor beyond 34 weeks, moreover after 34 weeks most centers do not administer antenatal prophylactic steroids. These practices are based on previous studies reporting neonatal mortality and morbidity in the late preterm period to be only slightly higher in comparison with term infants and whereas in the current scenario the difference is significant. Late preterm infants have 2-3-fold increased risk of morbidities such as hypothermia, hypoglycemia, delayed lung fluid clearance, respiratory distress, poor feeding, jaundice, sepsis, and readmission rates after initial hospital discharge. This leads to huge impact on the overall health care resources. In this review, we cover various aspects of these late preterm infants like etiology, immediate and long-term outcome.