Gestational diabetes mellitus (GDM) is a type of diabetes that develops during pregnancy due to hormonal and metabolic changes that impair the body’s ability to regulate blood sugar. Identifying the risk factors is crucial for early screening, prevention, and better pregnancy outcomes.
Here are the major factors that influence the risk of GDM, supported by research evidence.
1. High BMI / Obesity
Excess body weight before pregnancy is one of the strongest predictors of GDM. Obesity increases insulin resistance, making it harder for the body to regulate glucose during pregnancy.
👉 Takeaway: Achieving a healthy weight before pregnancy can significantly reduce GDM risk.
Reference: Najafi-Sharjabad F, et al. (2019). Pre-pregnancy BMI and gestational diabetes risk. PLOS One, 14(4):e0215372. doi:10.1371/journal.pone.0215372
2. Older Maternal Age
Women over 30–35 years face a significantly higher risk of developing GDM, likely due to age-related declines in insulin sensitivity and pancreatic function.
👉 Takeaway: Early screening is recommended for women planning pregnancies later in life.
Reference: Xu J, et al. (2023). Risk factors for gestational diabetes in Chinese women. Int J Gen Med, 16:3627–3637. doi:10.2147/IJGM.S409390
3. Family History of Diabetes
A genetic predisposition plays an important role. Women with a first-degree relative (parent or sibling) with type 2 diabetes are at higher risk of developing GDM.
👉 Takeaway: Women with a family history of diabetes should undergo glucose testing early in pregnancy.
Reference: Rani PR, Begum J. (2016). Screening and diagnosis of GDM. World J Diabetes, 7(19):1165–1171. PMC10663705
4. Previous Gestational Diabetes
Women who experienced GDM in a prior pregnancy face a much higher chance of recurrence in subsequent pregnancies.
👉 Takeaway: Preconception counseling and early glucose screening are essential for women with past GDM.
Reference: Chen Y, et al. (2025). Recurrence risk of GDM: systematic review. BMC Pregnancy Childbirth, 25:73. doi:10.1186/s12884-025-07367-9
5. Polycystic Ovary Syndrome (PCOS)
PCOS is characterised by insulin resistance and hormonal imbalances, both of which predispose women to GDM.
👉 Takeaway: Women with PCOS should be closely monitored for glucose changes during pregnancy.
Reference: Xu J, et al. (2023). Risk factors for gestational diabetes. Int J Gen Med, 16:3627–3637. doi:10.2147/IJGM.S409390
6. Excessive Weight Gain During Pregnancy
Gaining more weight than recommended during pregnancy increases insulin resistance and the likelihood of developing GDM, even in women who start pregnancy at a healthy weight.
👉 Takeaway: Following medical guidance on weight gain during pregnancy helps reduce GDM risk.
Reference: Chen Y, et al. (2025). Recurrence and risk factors for GDM. BMC Pregnancy Childbirth, 25:73. doi:10.1186/s12884-025-07367-9
7. Artificially Sweetened Drinks
Emerging research suggests that frequent consumption of artificially sweetened beverages (e.g., diet sodas and “zero sugar” drinks) may increase the risk of GDM. A recent study found that each additional artificially sweetened drink per week raised GDM risk by around 6%, and women consuming five or more per week had a significantly higher risk.
👉 Takeaway: Limiting artificially sweetened beverages before and during pregnancy may help lower the chance of GDM.
Reference: Menota B, Lassi Z, et al. (2025). Artificially sweetened beverage consumption lifts gestational diabetes risk. University of Adelaide / Diabetes Res Clin Pract.
Conclusion
Gestational diabetes is influenced by multiple factors, including pre-pregnancy weight, maternal age, family history, previous GDM, PCOS, weight gain during pregnancy, and even artificially sweetened drinks. Understanding these risks allows for early screening, healthier lifestyle choices, and better pregnancy outcomes.
