Researchers analyzed 104 studies involving nearly 36,000 pregnant women to see if lifestyle changes could prevent gestational diabetes, a type of diabetes that develops during pregnancy. They found that interventions focusing on exercise, diet, or a combination of both reduced the risk of gestational diabetes by 14-20%, depending on how the condition was measured. The benefits were strongest when women participated in group-based programs led by trained instructors, and when the focus was on physical activity. Importantly, all women benefited from these lifestyle changes, though the effect was slightly smaller for women with lower education levels.

The Quick Take

  • What they studied: Whether lifestyle changes like exercise and healthy eating during pregnancy can prevent gestational diabetes, and which approaches work best
  • Who participated: Nearly 36,000 pregnant women from 104 different research studies conducted between 1990 and 2025. The detailed information came from about 24,000 women across 54 studies
  • Key finding: Lifestyle interventions reduced gestational diabetes risk by 14-20%, with exercise-focused programs showing the strongest results. Group-based programs with trained instructors were more effective than individual approaches
  • What it means for you: If you’re pregnant or planning to become pregnant, participating in a structured exercise program or lifestyle intervention program may help reduce your risk of developing gestational diabetes. Group programs appear to work better than going it alone, and having a trained instructor makes a difference

The Research Details

This was a meta-analysis, which means researchers combined data from 104 different research studies to get a bigger, clearer picture. For 68% of the women studied (about 24,000), they had access to detailed individual participant data, allowing them to analyze specific information about each person. For the remaining women, they used summary information from the published studies. This two-step approach allowed them to both look at individual details and combine all available information to see the overall effects of lifestyle interventions.

The researchers looked at three main types of interventions: programs focused on physical activity, programs focused on diet changes, and programs that combined both approaches. They tracked whether women developed gestational diabetes using different diagnostic criteria, including the standard UK guidelines and international standards. They also examined whether the benefits varied depending on factors like age, weight, education level, and ethnicity.

By combining data from many studies, researchers can see patterns that might not be obvious in single studies. This approach is particularly powerful because it includes information from thousands of women across different countries and healthcare systems, making the results more reliable and applicable to different populations. The individual participant data allowed researchers to look at whether certain groups of women benefited more than others, which is important for tailoring recommendations

This study is highly reliable because it combined data from 104 randomized controlled trials, which are considered the gold standard in medical research. The large sample size of nearly 36,000 women provides strong statistical power. However, the results varied depending on how gestational diabetes was defined, suggesting that the specific diagnostic criteria used matters. The fact that benefits were consistent across different maternal characteristics (age, weight, ethnicity) strengthens the findings, though the slightly smaller benefit for women with lower education levels suggests that implementation strategies may need adjustment for different populations

What the Results Show

When researchers combined all available data, lifestyle interventions reduced gestational diabetes risk by about 20%, meaning that for every 100 pregnant women who participated in these programs, approximately 2-3 fewer would develop gestational diabetes compared to those who didn’t participate. When looking only at the most detailed studies with individual participant data, the reduction was about 14%, which is still meaningful but slightly smaller.

The type of intervention mattered somewhat. Physical activity-based programs ranked as the most effective approach for preventing gestational diabetes. Programs that combined exercise and diet changes also worked well. Importantly, the way programs were delivered made a difference: group-based programs were more effective than individual programs, and programs led by newly trained instructors were more effective than those led by experienced staff, suggesting that enthusiasm and fresh training approaches may be beneficial.

The benefits appeared consistent across most groups of women, regardless of age, weight, or ethnicity. However, women with higher education levels saw slightly greater benefits than those with lower education levels, though all groups still benefited from the interventions.

When researchers used the UK’s standard diagnostic criteria for gestational diabetes, lifestyle interventions did not show a significant reduction in risk. This suggests that the definition used to diagnose gestational diabetes matters significantly. When using international diagnostic standards (IADPSG criteria), the reduction was 14-18%, which is substantial. This variation highlights that the effectiveness of these interventions may depend on which diagnostic test is used, and healthcare providers should be aware of this when interpreting results

This research builds on previous studies showing that lifestyle changes can help prevent gestational diabetes. The major contribution of this analysis is confirming that these benefits hold true across many different populations and settings, and identifying which specific approaches work best. The finding that group-based programs with trained instructors are more effective than individual approaches provides new practical guidance that wasn’t as clearly established before

The study’s main limitation is that the results varied depending on how gestational diabetes was defined, with some diagnostic criteria showing clear benefits while others did not. This makes it harder to give a single, simple answer about how much risk reduction to expect. Additionally, while the study included women from many countries, the majority of participants were from developed nations, so results may not apply equally to all populations worldwide. The study also couldn’t determine exactly why group-based programs worked better or why newly trained instructors were more effective, so more research is needed to understand these mechanisms. Finally, the study measured whether women developed gestational diabetes but didn’t extensively examine other important outcomes like birth complications or long-term health effects

The Bottom Line

If you are pregnant or planning to become pregnant, participating in a structured lifestyle intervention program—particularly one focused on physical activity—appears to reduce your risk of gestational diabetes. Group-based programs are recommended over individual approaches. These programs should ideally be led by trained instructors. The evidence is moderate to strong for this recommendation, meaning the research is fairly convincing but not absolutely certain. All women appear to benefit, though women with higher education may see slightly larger benefits. Talk with your healthcare provider about available programs in your area

This research is relevant for all pregnant women, particularly those at higher risk for gestational diabetes (such as those who are overweight, have a family history of diabetes, or are over age 35). Women with lower education levels should know that they can still benefit from these programs, though they may need additional support or resources to participate effectively. Healthcare providers and public health officials should use this information to develop and promote accessible lifestyle intervention programs. Women with existing diabetes or other medical conditions should consult their healthcare provider before starting any new exercise program

Gestational diabetes typically develops in the second or third trimester of pregnancy, so starting lifestyle interventions early in pregnancy—ideally in the first or second trimester—gives the most time for benefits to develop. Most studies tracked outcomes throughout pregnancy, so benefits should be measurable by the time of delivery. However, maintaining these healthy habits throughout pregnancy is important for maximum benefit

Want to Apply This Research?

  • Track weekly exercise minutes (aim for 150 minutes of moderate activity per week during pregnancy) and daily servings of vegetables and whole grains. Log whether you’re participating in a group-based program or exercising with a partner, as social support appears to enhance effectiveness
  • Use the app to find or connect with local pregnancy exercise groups or lifestyle intervention programs in your area. Set weekly goals for physical activity that are safe during pregnancy, such as brisk walking, swimming, or prenatal yoga. Use the app’s reminder feature to encourage consistent participation in group sessions, as group-based programs showed better results than solo efforts
  • Track participation in structured programs weekly and monitor consistency of exercise habits. Set milestone goals for each trimester. Use the app to log any gestational diabetes screening results and share progress with your healthcare provider. Create accountability by sharing goals with group program members through the app’s social features

This research summary is for educational purposes only and should not replace professional medical advice. Gestational diabetes is a serious condition that requires medical supervision. Before starting any exercise program or lifestyle intervention during pregnancy, consult with your healthcare provider or obstetrician to ensure it is safe for your individual circumstances. This summary presents research findings but does not constitute medical advice or a treatment recommendation. Always follow your healthcare provider’s guidance regarding gestational diabetes screening, diagnosis, and management. If you have been diagnosed with gestational diabetes, work with your healthcare team to develop an appropriate treatment plan.