Researchers looked at 86 studies involving over 28,000 pregnant women to figure out which lifestyle changes work best for managing weight gain during pregnancy. They found that all types of lifestyle interventions—including diet changes, exercise, or a combination of both—helped reduce excessive weight gain. However, the research shows that different approaches work better for different women depending on factors like their starting weight and cholesterol levels. The most effective approach was combining diet and exercise changes, especially when started early in pregnancy. This research suggests that doctors should personalize pregnancy weight management plans rather than using the same approach for everyone.

The Quick Take

  • What they studied: Which lifestyle changes (diet, exercise, or both) work best to help pregnant women avoid gaining too much weight, and whether certain women benefit more from specific approaches.
  • Who participated: Over 28,000 pregnant women from 86 different research studies. The women had different starting weights, ages, and backgrounds, allowing researchers to see if the same approach worked for everyone.
  • Key finding: All lifestyle interventions reduced excessive weight gain during pregnancy. Combined diet and exercise programs worked best, especially when started in the first or early second trimester. Diet-only programs worked well for women with normal starting weight, while combined programs worked better for women with higher ‘good cholesterol’ levels.
  • What it means for you: If you’re pregnant or planning to become pregnant, talk with your doctor about personalized weight management. A combination of healthy eating and safe exercise, started early in pregnancy, appears most effective. However, the best approach for you depends on your individual health profile, so one-size-fits-all advice may not be ideal.

The Research Details

This was a systematic review and meta-analysis, which means researchers searched through medical databases to find all high-quality studies about lifestyle interventions during pregnancy and weight gain. They identified 86 studies published up to March 2025 that tested whether diet changes, exercise, or a combination of both could help manage pregnancy weight gain. The researchers then combined the results from all these studies to see overall patterns and used statistical methods to examine whether certain groups of women benefited more from specific interventions.

The researchers looked at many different participant characteristics to understand who benefited most, including starting weight (BMI), age, race and ethnicity, employment status, and cholesterol levels. They used advanced statistical techniques called meta-regression and subgroup analysis to determine if these characteristics affected how well each intervention worked.

This approach is powerful because it combines evidence from thousands of women across many different studies, giving a much clearer picture than any single study could provide. However, it relies on the quality and completeness of the original studies included.

Understanding which interventions work best for which women is important because pregnancy is a unique time when weight management affects both the mother’s and baby’s health. Excessive weight gain during pregnancy increases risks for complications like gestational diabetes and high blood pressure. By identifying which approaches work best for different women, doctors can provide more personalized, effective recommendations rather than giving the same advice to everyone.

This study is a meta-analysis of 86 studies, which is a strong research design that combines evidence from many sources. The large sample size (over 28,000 women) increases confidence in the findings. However, the researchers noted that not all original studies reported detailed information about all participant characteristics, which limited their ability to examine some factors. The studies included were both randomized controlled trials (the gold standard) and non-randomized controlled trials, which may have different levels of reliability.

What the Results Show

All three types of lifestyle interventions—diet alone, exercise alone, and combined diet plus exercise—successfully reduced excessive weight gain during pregnancy. However, combined interventions (diet plus exercise) were most effective, particularly when started early in pregnancy. When started at the very beginning of pregnancy, combined interventions reduced weight gain by about 0.68 kilograms more than usual care. When started in the early second trimester (weeks 13-17), they reduced weight gain by about 0.83 kilograms more.

The research revealed important differences based on women’s starting characteristics. Diet-only interventions worked particularly well for women who started pregnancy at a normal weight, reducing their weight gain by about 1.33 kilograms compared to other weight categories. This suggests that women with normal starting weight may respond better to dietary changes alone.

For women with higher levels of ‘good cholesterol’ (HDL-C) at the start of the program, combined diet and exercise interventions were especially effective. This finding suggests that cholesterol levels may indicate which women will benefit most from comprehensive lifestyle programs.

These results support the idea that pregnancy weight management should be personalized based on individual characteristics rather than applying the same approach to all women.

The research confirmed that lifestyle interventions reduce the risk of excessive weight gain during pregnancy, which in turn reduces complications for both mother and baby. The timing of intervention initiation appeared important—starting early in pregnancy (first trimester or early second trimester) produced better results than starting later. The study also highlighted that employment status and other social factors may play a role in intervention effectiveness, though more research is needed to understand these connections.

This research builds on growing evidence that lifestyle interventions during pregnancy are effective. Previous studies have shown that excessive weight gain during pregnancy increases health risks, but this study goes further by identifying which specific approaches work best for different women. The finding that combined interventions work better than single approaches aligns with other recent research suggesting that comprehensive lifestyle changes are more effective than isolated interventions.

The researchers noted several important limitations. Not all original studies reported complete information about participant characteristics, which prevented them from examining some factors that might affect intervention success. The studies varied in quality and design, which could affect the overall conclusions. Additionally, the research focused mainly on physiological characteristics (like weight and cholesterol) but had limited information about social factors (like income, education, and support systems) that might also influence whether women can successfully follow lifestyle interventions. The researchers emphasize that future studies should include more detailed information about both physical and social characteristics to better understand how to help all women succeed.

The Bottom Line

If you’re pregnant or planning pregnancy, discuss personalized weight management with your healthcare provider. A combination of healthy eating and safe, pregnancy-appropriate exercise, started as early as possible, appears most effective based on current evidence (moderate confidence). If you have a normal starting weight, diet changes alone may be sufficient. If you have other health factors, a combined approach is likely better. Always work with your doctor to create a plan tailored to your individual health profile and circumstances.

This research is most relevant for pregnant women and those planning pregnancy, particularly those concerned about excessive weight gain. Healthcare providers caring for pregnant women should consider these findings when developing weight management recommendations. Women with normal starting weight, those with higher good cholesterol levels, and those able to start interventions early in pregnancy may see the most benefit. However, the research suggests that all pregnant women could benefit from some form of lifestyle intervention, though the specific approach should be personalized.

Weight management benefits from lifestyle interventions typically become apparent over weeks to months during pregnancy. Starting interventions early (first trimester) appears to produce better results than starting later. The full benefits for both mother and baby health may not be apparent until after delivery and in the postpartum period.

Want to Apply This Research?

  • Track weekly weight gain (aim for 1-1.5 pounds per week in second and third trimesters for normal-weight women) along with daily diet quality (servings of fruits, vegetables, whole grains) and minutes of pregnancy-safe physical activity. Compare actual weight gain to recommended ranges for your starting weight category.
  • Set a specific, achievable goal such as: ‘I will do 30 minutes of pregnancy-safe walking 3 times per week’ combined with ‘I will add one extra vegetable serving to my lunch daily.’ Start these changes as early in pregnancy as possible for best results.
  • Use the app to log weekly weight, dietary changes, and exercise consistently throughout pregnancy. Review monthly trends rather than daily fluctuations. Share data with your healthcare provider at prenatal visits to adjust the plan if needed based on your individual progress and health factors.

This research summary is for educational purposes only and should not replace professional medical advice. Pregnancy weight management is highly individual and depends on your specific health status, starting weight, and medical history. Always consult with your obstetrician, midwife, or healthcare provider before starting any diet or exercise program during pregnancy. This research suggests general patterns but may not apply to your specific situation. If you have gestational diabetes, high blood pressure, or other pregnancy complications, your healthcare provider may recommend different approaches than those discussed here.