((C-023)) (C-023) A Profile Study of Characteristics and Treatment of Preterm and Term Births in the United Sates: An Analysis of the CDC WONDER Database, 2016-2023

Background: Maternal and infant characteristics, along with treatments are critical in preventing pre-term births and reducing infant mortality.

Objectives: This study aims to profile US births by gestational age (GA) using data-driven approach, moving beyond prior studies focused solely on individual factors.

Methods: Aggregated data on births between 28-41weeks GA from the CDC WONDER database (2016-2023) were analyzed. Maternal characteristics, prenatal care, maternal/pregnancy risk factors and morbidities, labor/delivery characteristics, infant conditions, and treatment by gestational week were profiled using unsupervised hierarchical clustering analysis. Patterns were summarized and visualized with heatmaps.

Results: Four clusters were identified by GA: 28-31 weeks, 32-34 weeks, 35-36 weeks and 39-41 weeks. Among them, the 28-31-week and 37-41-week clusters displayed distinct patterns. Compared with the 37-41-week cluster, the 28-31-week cluster showed higher rates of adverse maternal and infant characteristics (e.g., delayed prenatal care, maternal morbidities, cesarean delivery) and required intensive interventions (e.g., surfactant therapy, infant transfer, NICU admission), with worse outcomes (e.g., abnormal conditions, low breastfeeding rates at discharge). The 32-34-week and 35-36-week clusters exhibited transitional profiles between the two aforementioned distinct groups, with the notable exception of high gestational diabetes rates in the two clusters. To understand changes in profile over time, rate differences between 2016 and 2023 were examined. An increase in gestation diabetes (especially among infants born at 34-39 weeks) and hypertension was observed. Additionally, the use of assistive reproductive technology and infertility treatments increased for infants born at 37-41 week. While the use of assisted ventilation and steroid (especially for infants of 35 and 36 weeks) became more common in clinical practice, the rates of infant transfer (28-36 weeks only), antibiotics for suspected neonatal sepsis, congenital anomalies, and gestational clamps declined over the seven-year period.

Conclusions: This study provides a comprehensive profile of maternal and infant characteristics and treatments across preterm and term births in the US, revealing dynamic patterns influenced by maternal morbidities and evolving clinical practices. Further studies using patient-level data are needed to validate these findings.