Abstract
Abstract
Background
Preterm birth (PTB) is a leading cause of global neonatal mortality and long‐term complications. Placental growth factor (PlGF) is a key regulator of placental vascular development; however, prospective evidence regarding the association between its first‐trimester levels and the risk of PTB remains insufficient. This study aimed to investigate the association between first‐trimester PlGF levels and PTB, including its subtypes.
Methods
This was a single‐center prospective cohort study. From August 2023 to October 2025, a total of 1448 women with singleton pregnancies at 11–13 + 6 weeks of gestation were enrolled at Peking University International Hospital. Peripheral blood was collected during the first trimester for the measurement of PlGF concentration. Raw PlGF concentrations (pg/mL) were converted to multiples of the median (MoM) using the Fetal Medicine Foundation online calculator. The primary outcome was PTB, defined as delivery between 28 and
Results
Among the 1448 participants, 80 (5.5%) experienced PTB. Lower first‐trimester PlGF‐MoM was associated with an increased risk of PTB after adjustment for maternal characteristics (adjusted risk ratio = 0.303, 95% confidence interval: 0.14–0.61). Restricted cubic spline analysis demonstrated a significant nonlinear association (
p
for nonlinearity P
= 0.01), although predictive performance remained limited.
Conclusion
Lower first‐trimester PlGF–MoM was associated with an increased risk of PTB in this prospective cohort, showing a nonlinear exposure–response pattern. First‐trimester PlGF might provide additional information for early identification of women at higher risk of PTB; however, its clinical utility requires validation in larger and diverse populations.