Which of the following is a risk factor for developing gestational diabetes?

A previous history of diabetes, particularly gestational diabetes in a previous pregnancy, is a significant risk factor for developing gestational diabetes in subsequent pregnancies. This is because individuals who have experienced gestational diabetes are more likely to have insulin resistance, which can re-emerge during later pregnancies. Therefore, their physiological response to the increased demands of pregnancy may lead to hyperglycemia, resulting in gestational diabetes.

Understanding gestational diabetes involves recognizing how multiple factors can influence its development. For example, advancing age (the option mentioning being over 25 years) can also be a contributing factor; however, it is less predictive than having had gestational diabetes before. Similarly, maintaining a high-fiber diet is often associated with better blood sugar control and does not constitute a risk factor. Being underweight prior to pregnancy generally does not correlate with an increased risk of gestational diabetes, as the condition is more often linked with obesity or overweight status. Therefore, previous history of diabetes stands out as the integral risk factor for the condition in question.