Temporal Trends in Preterm Birth Associated With Hypertensive Disorders of Pregnancy in Victoria, Australia: A Population-Based Interrupted Time-Series Study

Abstract

Objectives: Hypertensive disorders of pregnancy (HDP) are a leading reason for medically indicated preterm birth (PTB), yet their contribution to population-level PTB trends is poorly understood. We examined temporal trends in PTB overall and HDP-associated PTB in Victoria over an 11-year period spanning the COVID-19 pandemic, and distinguished changes in HDP prevalence from changes in preterm delivery among affected pregnancies. Study Type: Population-based interrupted time-series study using seasonal autoregressive integrated moving average (SARIMA) models, with July 2018 (launch of a national preterm birth prevention program) pre-specified as a temporal reference point. Setting: All hospi..