Association between dietary protein intake and preterm birth in pregnant women with gestational diabetes mellitus: the WeBirth cohort study.

BACKGROUND AND OBJECTIVES: The distribution of dietary macronutrients is essential for blood glucose management in patients with gestational diabetes mellitus (GDM). However, the relationship between dietary protein intake and the risk of preterm birth remains unclear. Here, we aim to investigate the prospective association between dietary protein intake and preterm birth in patients with GDM. METHODS AND STUDY DESIGN: We included 1756 GDM patients and assessed dietary protein patterns by constructing total protein index (TPI), animal protein index (API), and plant protein index (PPI) using data collected from food frequency questionnaires (FFQ). RESULTS: We found that individuals in the highest quartile of TPI (OR: 2.75, 95% CI: 0.81 to 9.22) and API (OR: 3.64, 95% CI: 1.48 to 9.47) had a significantly higher risk of preterm birth compared to those in the lowest quartile. CONCLUSIONS: This study suggests that increasing protein intake, especially from animal sources, was associated with a greater risk of preterm birth in patients with GDM.