Last updated on:May 19th, 2022
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Gestational diabetes mellitus (GDM) is a condition in which a non-diabetic woman develops chronic hyperglycemia during pregnancy. This hyperglycemia, in most cases, is the result of impaired glucose tolerance secondary to pancreatic β-cell dysfunction, in a background of chronic insulin resistance or diminished insulin production. GDM tends to develop during the second or third trimester. It is most often diagnosed during the universal screening for GDM conducted at 24-28 weeks of gestation.
Risk factor: age
A maternal age ≥40 years is associated with an increased risk of impaired glucose tolerance during pregnancy.
Risk factor: ethnicity
Women of African-American, Hispanic, Middle-Eastern, Native American, Pacific Islander, and South Asian origin are more likely to develop GDM.
Risk factor: past GDM
Around one-third of women with GDM develop the condition in a future pregnancy.
Risk factor: positive family history
The presence of a first-degree relative with diabetes mellitus or a sister with GDM increases the risk of developing GDM.
Risk factor: sedentary lifestyle
An inactive lifestyle and westernized diet are both modifiable risk factors for GDM.
Risk factor: dysglycemic medications
Regular treatment with corticosteroids, antipsychotics, or other medications with an anti-insulin effect is another modifiable risk factor for GDM.
Risk factor: high gestational weight gain
During the period of gestation, a maternal weight gain >22 lb/year (>10kg/year) confers a more than two-fold increased risk for GDM.
Risk factor: weight before pregnancy
Pre-pregnancy obesity increases the risk for GDM.
Risk factor: High neonatal weight in a previous pregnancy
Previously delivering a baby >9 lb (4 kg) increases the risk for GDM.