Infants Born at Late Preterm Gestation: Management during the Birth Hospitalization.

OBJECTIVE: To examine the admission practices, frequency of common clinical morbidities, and rates of medical intervention in infants born at 34-36 weeks gestational age (GA, late preterm). STUDY DESIGN: This retrospective, single institution, cohort study analyzed electronic health records of infants born late preterm from 2019 through 2021. Infants with known congenital anomalies necessitating neonatal intensive care unit admission were excluded. Analysis included descriptive and inferential statistics. RESULTS: The study included 1022 infants: 209 (21%) 34 weeks GA, 263 (26%) 35 weeks GA, and 550 (54%) 36 weeks GA. Sixty-three percent of infants at 35 weeks GA and 78% of infants of 36 weeks GA remained in well newborn care throughout the birth hospitalization; infants born at 34 weeks GA were ineligible for well newborn care. The need for respiratory support was 32%, 18%, and 11% in infants of 34, 35, and 36 weeks GA, respectively. Supplemental tube feeds were administered in 55%, 24%, and 8% of infants of 34, 35, and 36 weeks GA, respectively. Most infants born at 34 weeks GA (91%) were placed in an incubator; this was less frequent in infants at 35 (37%) and 36 weeks (16%). Tachypnea, hypoglycemia, and hypothermia were noted in 40%, 61%, and 57% of infants, respectively. A subset of these infants (30% with tachypnea, 23% with hypoglycemia, and 46% with hypothermia) required medical intervention for these abnormalities. CONCLUSIONS: This single-center study provides an outlook on the care of infants born late preterm. Multicenter studies can contextualize these findings in order to develop clinical benchmarks and quality markers for this large population of infants.

The Effect of Early Limited Formula on Breastfeeding, Readmission, and Intestinal Microbiota: A Randomized Clinical Trial.

OBJECTIVE: To determine whether using 10 mL formula after each breastfeeding before copious maternal milk production affects breastfeeding duration, readmission, and intestinal microbiota through 1 month of age. STUDY DESIGN: In this randomized controlled trial, we enrolled 164 exclusively breastfeeding newborns, 24-72 hours old, whose weight loss was ≥75th percentile for age, and whose mothers had not yet begun mature milk production. Enrolled newborns were assigned randomly to either supplement breastfeeding with early limited formula (ELF), 10 mL of formula after each breastfeeding stopped at the onset of copious maternal milk production (intervention), or to continue exclusive breastfeeding (control). Outcomes assessed through 1 month included breastfeeding duration, readmission, and intestinal microbiota. RESULTS: At 1 week of age, 95.8% of infants receiving ELF and 93.5% of control infants were still breastfeeding (P > .5); readmission occurred for 4 (4.8%) control infants and none of the infants receiving ELF (P = .06). At 1 month of age, 86.5% of infants receiving ELF and 89.7% of control infants were still breastfeeding (P > .5); 54.6% of infants receiving ELF and 65.8% of controls were breastfeeding without formula (P = .18). ELF did not lead to decreased abundance of Lactobacillus or Bifidobacterium and was not associated with expansion of Clostridium. CONCLUSION: In this population of healthy newborns with weight loss ≥75th percentile, ELF did not interfere with breastfeeding at 1 month, breastfeeding without formula at 1 month, or intestinal microbiota. ELF may be an important therapeutic option for newborns with the potential to reduce readmission rates. TRIAL REGISTRATION: Clinicaltrials.gov: NCT02313181.

Total serum bilirubin exceeding exchange transfusion thresholds in the setting of universal screening.

OBJECTIVE: To describe the incidence and predictors of total serum bilirubin (TSB) levels that meet or exceed American Academy of Pediatrics (AAP) exchange transfusion (ET) thresholds in the setting of universal screening. STUDY DESIGN: We conducted a retrospective cohort analysis of electronic data on 18 089 newborns ≥35 weeks gestation born at Northern California Kaiser Permanente Medical Care Program hospitals implementing universal TSB screening in 2005 to 2007, with chart review for subjects with TSB levels reaching the AAP threshold for ET. RESULTS: The outcome developed in 22 infants (0.12%); 14 (63.6%) were <38 weeks gestation. Only one infant received an ET; none of the infants had documented sequelae. The first TSB was at least high-intermediate risk on the AAP risk-nomogram for all 22 infants and high-risk for those ≥38 weeks, but was less than the phototherapy level in 15 infants (68%). Of these 15 infants, 2 failed phototherapy and 13 did not have a TSB repeated in <24 hours. However, re-testing all infants at high-intermediate risk or greater would have required 2166 additional bilirubin tests. CONCLUSION: Screening was sensitive but not specific for predicting exchange threshold.