At what gestational age does gestational diabetes typically show itself?

Gestational diabetes is typically diagnosed in the second trimester of pregnancy, generally between 24 and 28 weeks of gestation. This timing aligns with the physiological changes that occur during pregnancy, where hormones such as cortisol and human placental lactogen increase insulin resistance. As a result, some women may develop elevated blood glucose levels during this period, even if they did not have diabetes prior to pregnancy.

Detecting gestational diabetes in the second trimester enables appropriate management to reduce complications for both the mother and the baby. If left undiagnosed and untreated, gestational diabetes can lead to several adverse outcomes, including larger birth weight (macrosomia), increased risk of cesarean delivery, and the potential for the mother to develop type 2 diabetes postpartum.

In contrast, gestational diabetes rarely presents in the first trimester, as blood sugar levels are generally well-regulated during the early stages of pregnancy. Diagnosing it immediately after birth doesn’t apply, as gestational diabetes is defined by its onset during pregnancy, not after delivery. By understanding this timeline, healthcare providers can better monitor and intervene to support maternal and fetal health.