Gestational Diabetes Mellitus (GDM) Home A-Z Health Information Health Library A-Z Gestational Diabetes Mellitus (GDM) Overview Gestational diabetes mellitus (GDM) refers to a form of diabetes arising during pregnancy and usually resolves post childbirth. It is caused by hormonal changes occurring during pregnancy that tend to affect insulin sensitivity. Symptoms Often mild or absent, but GDM can lead to complications like high birth weight and preterm delivery (childbirth before 37 weeks of pregnancy). Diagnosis Screening tests like the GTT during pregnancy. Treatment & Prevention Dietary changesRegular physical activitySometimes insulin therapy to regulate blood sugar levels.Monitoring blood sugar levels and following medical advice are crucial for a healthy pregnancy and reducing the likelihood of developing type 2 diabetes later.