Favourable and optimal pregnancy outcomes depend on women entering pregnancy with full nutrient stores, sound eating habits, and healthy body weight. Metabolic syndrome is a cluster of at least three of the five medical conditions: raised fasting plasma glucose, abdominal obesity, high serum triglycerides, low serum high-density lipoprotein and high blood pressure. This study aims to investigate the progression of metabolic syndrome components during pregnancy, and adverse pregnancy outcomes in the mother-infant cohort study.