Neonatal morbidity of late preterm compared with early term neonates

Nuno Lourenço, Marco Fernandes, Clara Gomes, Cristina Resende


DOI: 10.15448/1980-6108.2017.1.25876

Aims: To evaluate and compare neonatal morbidity between late-preterm infants (LPTI) and early term infants (ETI).

Methods: Retrospective cross-sectional study, including live births at a regional referral maternity hospital in Portugal, in the years 2014 and 2015, with gestational age between 340/7 and 386/7 weeks. LPTI (340/7-366/7 weeks) were considered as cases and ETI (370/7-386/7 weeks) were considered controls. Neonates with congenital malformations, lack of prenatal care and hospitalization for social/maternal reasons were excluded. We evaluated and compared neonatal morbidity between the two groups, using Student's t-test for comparison between means (continuous variables) and Chi-square or Fisher's test for comparison between categorical variables. Odds ratio (OR) was calculated and adjusted (aOR) to birth weight, maternal disease, type of birth and multiple pregnancy. A value of p <0,05 was considered of statistical significance.

Results: A total of 1,745 neonates were evaluated: 324 cases (LPTI) and 1,421 controls (ETI). LPTI was associated with a higher frequency of maternal hypertension and gestational diabetes and higher rates of twinning and cesarean section. LPTI also had a higher risk for resuscitation (OR = 2.0 - 95%CI 1.3-3.0); hypoglycemia (aOR = 4.9 - 95%CI 2.9-8.2); hyperbilirubinemia (aOR = 4.8 - 95%CI 3.7-6.2), transient tachypnea (aOR = 6.4 - 95%CI 4.0-10.3); eating difficulties (aOR = 6.6 - 95%CI 4.8-8.9); sepsis (aOR = 4.4 - 95%CI 4.8-8.9); hospital stay ≥5 days (aOR = 8.6 - 95%CI 6.6-11.3); and lower exclusive breastfeeding rate (aOR = 0.2 - 95%CI 0.15-0.3).

Conclusions: In comparison to ETI, LPTI presented a higher risk of morbidity. This study reinforces the need for appropriate clinical follow-up of LPTI in the neonatal period.


infant, newborn; infant, premature; morbidity.


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