According to Gram Research analysis, a 2026 cohort study of 8,238 mother-child pairs found that children whose mothers had poor cardiovascular health during pregnancy were 62% more likely to experience developmental delays by age 4 compared to children whose mothers had excellent cardiovascular health. Maternal cardiovascular health was measured across eight factors including diet, exercise, sleep, weight, blood pressure, and blood sugar. The strongest associations appeared in social skills and fine motor development, suggesting that maternal heart health during pregnancy may influence multiple aspects of child development.
A major study of over 8,200 mothers and children in Japan found that a mother’s heart and overall cardiovascular health during pregnancy may influence her child’s development at age 4. Researchers measured mothers’ health using eight key factors like diet, exercise, sleep, weight, and blood pressure. Children whose mothers had poor cardiovascular health during pregnancy were significantly more likely to show developmental delays in areas like communication, movement, and social skills. This research suggests that taking care of mom’s health before and during pregnancy could have lasting benefits for how children grow and develop.
Key Statistics
A 2026 cohort study of 8,238 mother-child pairs in Japan found that children whose mothers had low cardiovascular health during pregnancy were 62% more likely to experience developmental delays by age 4 compared to those with high maternal cardiovascular health.
Among 8,238 mother-child pairs, only 8.8% of children whose mothers had high cardiovascular health during pregnancy showed developmental delays, compared to 16.8% of children whose mothers had low cardiovascular health.
In a 2026 study of over 8,200 Japanese families, low maternal cardiovascular health during pregnancy was associated with a 123% increased risk of delays in personal-social skills (like sharing and following rules) in 4-year-old children.
A 2026 cohort study found that moderate maternal cardiovascular health during pregnancy increased offspring developmental delay risk by 30% compared to high maternal cardiovascular health, while low maternal cardiovascular health increased risk by 62%.
The Quick Take
- What they studied: Whether a mother’s heart and overall cardiovascular health during pregnancy affects her child’s development and learning abilities by age 4.
- Who participated: Over 8,200 mother-child pairs from Japan, with children assessed at an average age of 4.1 years. About 52% were boys. Mothers were enrolled between 2013 and 2017 and followed for 5 years.
- Key finding: Children whose mothers had poor cardiovascular health during pregnancy were 62% more likely to experience developmental delays compared to children whose mothers had excellent cardiovascular health. The effect was strongest for social and personal skills.
- What it means for you: Maintaining good cardiovascular health during pregnancy—through healthy diet, regular exercise, good sleep, and managing weight and blood pressure—may help support your child’s development. However, this is observational research, so it shows a connection but doesn’t prove cause-and-effect.
The Research Details
This was a cohort study, which means researchers followed a large group of mothers and their children over time to see what happened. Mothers were enrolled between July 2013 and March 2017 at hospitals and clinics in Japan, and children were tracked until age 4. Researchers measured mothers’ cardiovascular health using eight key metrics called Life’s Essential 8: diet quality, physical activity, nicotine exposure, sleep quality, body mass index (BMI), blood lipids (cholesterol), blood glucose (blood sugar), and blood pressure. Each metric was scored from 0 (worst) to 100 (best), and mothers were grouped into three categories: high health (80-100), moderate health (50-79), or low health (0-49). At age 4, mothers completed a validated questionnaire about their child’s development across five areas: communication, gross motor skills (like running and jumping), fine motor skills (like drawing and writing), problem-solving, and personal-social skills (like sharing and following rules). Developmental delay was defined as scoring 2 or more standard deviations below average in any domain.
This research approach is important because it allows researchers to track real families over several years and see how maternal health during a critical period (pregnancy) relates to child outcomes. By measuring multiple aspects of cardiovascular health together rather than just one factor, the study captures a more complete picture of maternal wellness. The study also examined specific developmental domains rather than just overall development, which helps identify where problems might emerge.
This study has several strengths: it’s large (over 8,200 pairs), it followed families for 5 years, it used validated measurement tools for both maternal health and child development, and it was published in a high-quality medical journal (JAMA Network Open). However, the study only included Japanese families, so results may not apply equally to other populations. Additionally, about 57% of eligible families didn’t complete the study, which could affect results if those families were systematically different from those who stayed. The study shows association, not proof of cause-and-effect.
What the Results Show
Among the 8,238 mother-child pairs analyzed, children whose mothers had high cardiovascular health during pregnancy had the lowest rates of developmental delay (8.8%). In contrast, children whose mothers had moderate cardiovascular health had higher delay rates (12.1%), and those with low maternal cardiovascular health had the highest rates (16.8%). When compared to the high cardiovascular health group, children whose mothers had moderate health were 30% more likely to experience developmental delay, while those with low maternal health were 62% more likely to experience delay. The relationship was consistent across all five developmental domains measured, meaning low maternal cardiovascular health was associated with delays in communication, movement skills, problem-solving, and social abilities. The strongest association was in the personal-social domain (social skills and relationships), where low maternal cardiovascular health increased the risk of delay by 123%. The communication domain showed the weakest association, though it was still elevated.
The study found that the effect of maternal cardiovascular health was dose-dependent, meaning worse health was associated with progressively higher risk of developmental delay. This pattern held true across all five developmental domains, suggesting that maternal cardiovascular health during pregnancy may influence multiple aspects of child development rather than just one area. The researchers also noted that the personal-social and fine motor domains showed particularly strong associations with maternal cardiovascular health, suggesting these areas may be especially sensitive to the intrauterine environment.
While previous research has shown that maternal health during pregnancy affects child outcomes, this is one of the first large studies to examine the relationship between comprehensive cardiovascular health (measured across eight factors) and developmental delay specifically. Most prior research focused on individual factors like maternal obesity or gestational diabetes rather than overall cardiovascular wellness. This study’s findings align with the broader understanding that pregnancy is a critical window when maternal health can influence fetal development, but it extends this knowledge by showing that multiple cardiovascular factors together may be particularly important.
The study has several important limitations. First, it only included families from one region of Japan, so results may not apply to other populations with different genetics, healthcare systems, or lifestyles. Second, about 43% of eligible families participated, and we don’t know if those who didn’t participate were systematically different. Third, developmental delay was assessed by mothers using a questionnaire rather than by trained professionals, which could introduce bias. Fourth, the study measured maternal cardiovascular health at one point in time during pregnancy, but health can change throughout pregnancy. Finally, this study shows that maternal cardiovascular health and child developmental delay are connected, but it cannot prove that poor maternal health causes developmental delay—other factors could explain the relationship.
The Bottom Line
Based on this research, pregnant women and those planning pregnancy should prioritize cardiovascular health through: eating a healthy diet rich in fruits, vegetables, and whole grains; getting regular physical activity (as approved by their doctor); maintaining a healthy weight; getting 7-9 hours of quality sleep; managing blood pressure and cholesterol; avoiding nicotine; and managing blood sugar levels. These recommendations align with standard prenatal care guidance. However, this is observational research showing association, not proof of cause-and-effect, so these recommendations should be discussed with your healthcare provider. The evidence is moderately strong (large study, consistent findings across domains) but not definitive.
This research is most relevant to women who are pregnant or planning to become pregnant, as well as healthcare providers who counsel pregnant women. It’s also important for public health officials considering prenatal care guidelines. The findings suggest that comprehensive cardiovascular health during pregnancy may be important for child development. However, the study was conducted in Japan, so applicability to other populations should be considered. Women with existing cardiovascular conditions should work closely with their healthcare team, as this research doesn’t provide specific guidance for managing pre-existing health conditions during pregnancy.
Developmental delays identified in this study were measured at age 4 years. Some developmental differences may be apparent earlier (by age 2-3), while others may not become obvious until school age. If you’re pregnant or planning pregnancy, focusing on cardiovascular health now could support your child’s development over the coming years. However, developmental outcomes are influenced by many factors beyond maternal pregnancy health, including genetics, postnatal environment, nutrition, and early childhood experiences.
Frequently Asked Questions
Can a mother’s heart health during pregnancy affect her baby’s development?
Research shows a connection: children whose mothers had poor cardiovascular health during pregnancy were 62% more likely to experience developmental delays by age 4. Maternal health factors like diet, exercise, sleep, weight, blood pressure, and blood sugar appear to influence child development, though more research is needed to understand exactly how.
What specific developmental areas are affected by maternal cardiovascular health?
A 2026 study found associations across all five developmental domains: communication, gross motor skills, fine motor skills, problem-solving, and personal-social skills. The strongest effect was on social skills (123% increased risk with low maternal health) and fine motor skills, while communication showed the weakest association.
Is it too late to improve cardiovascular health during pregnancy?
This study measured health at one point during pregnancy, so it’s unclear when improvements matter most. However, standard prenatal care recommends maintaining healthy diet, exercise, sleep, and managing blood pressure throughout pregnancy. Discuss specific changes with your healthcare provider, as recommendations vary based on individual health.
What are the eight cardiovascular health factors measured in this study?
The study measured: diet quality, physical activity, nicotine exposure, sleep health, body mass index (weight), blood lipids (cholesterol), blood glucose (blood sugar), and blood pressure. Together, these factors create a comprehensive picture of cardiovascular wellness during pregnancy.
Does this study prove that poor maternal health causes developmental delays?
No, this study shows an association between maternal cardiovascular health and child developmental delays, but doesn’t prove cause-and-effect. Other factors could explain the relationship. The study followed real families over time, which is strong evidence, but more research is needed to confirm causation.
Want to Apply This Research?
- Track the eight cardiovascular health metrics during pregnancy: daily steps or exercise minutes, sleep duration and quality, meals with vegetables/whole grains, blood pressure readings (if monitored), weight at prenatal visits, and nicotine/tobacco exposure. Create a simple weekly scorecard rating each area as ‘good,’ ‘fair,’ or ’needs work.’
- Set one specific cardiovascular health goal for this week: add a 20-minute walk, add one vegetable to dinner, go to bed 30 minutes earlier, or schedule a blood pressure check. Log completion daily and celebrate small wins to build momentum.
- Use the app to track trends in cardiovascular health metrics across trimesters. Create reminders for prenatal appointments where blood pressure, weight, and glucose are measured. Set monthly goals to improve one metric at a time rather than trying to change everything at once. Share progress with your healthcare provider.
This research shows an association between maternal cardiovascular health during pregnancy and child developmental outcomes, but does not establish definitive cause-and-effect. The study was conducted in Japan and may not apply equally to all populations. Developmental delay is influenced by many factors beyond maternal pregnancy health, including genetics, postnatal environment, and early childhood experiences. If you are pregnant or planning pregnancy and have concerns about cardiovascular health or your child’s development, consult with your healthcare provider or pediatrician. This information is for educational purposes and should not replace professional medical advice. Pregnant women with existing cardiovascular conditions should work closely with their healthcare team for personalized guidance.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.