Effetti dell'educazione dietetica basata sul modello transteorico e sul carico cognitivo sul controllo glicemico e sugli esiti della gravidanza nel diabete mellito gestazionale: uno studio retrospettivo con abbinamento per propensity score

1. Introduction

Gestational diabetes mellitus (GDM) is a type of diabetes caused by abnormal glucose tolerance due to maternal hormonal imbalance, insulin resistance, and insufficient insulin secretion during pregnancy. It is a common complication in the perinatal period. [ , ] According to survey data, the global prevalence of GDM ranges from 9% to 25%, while in China, it is between 13.0% and 20.9%. In recent years, with changes in lifestyle and the continuous relaxation of fertility policies, the number of high-risk pregnant women, such as those of advanced maternal age and those who are overweight, has been steadily increasing. Consequently, the incidence of GDM in China has been rising annually, making it a hot topic in the field of maternal-fetal medicine. [ , ]

Pregnant women with GDM often experience persistently elevated blood glucose levels and endocrine and metabolic disorders, which can lead to risks such as abnormal amniotic fluid levels and premature rupture of membranes, resulting in adverse pregnancy outcomes including macrosomia and neonatal death. These complications pose a serious threat to the safety of both mother and child. [ , ]

Clinical studies have shown that most pregnant women with GDM lack adequate knowledge about GDM and have weak self-management awareness, leading to poor glycemic control and an increased risk of maternal and fetal complications. [ ] Therefore, exploring scientific and practical educational strategies is of great significance for controlling blood glucose levels and improving pregnancy outcomes in pregnant women with GDM.

Cognitive load-based education based on the transtheoretical model (TTM) integrates various theories based on the behavior change model. It aims to understand the dynamic psychological needs and willingness for self-management behavior of pregnant women during the intervention process. By providing targeted dietary health education according to the cognitive characteristics, psychological load levels, and individual needs of pregnant women with GDM, this educational approach seeks to effectively stimulate behavior change awareness and self-efficacy, enhance self-management ability, and consequently improve maternal and neonatal outcomes. [ , ] The TTM has also been widely applied in the management of chronic diseases such as coronary heart disease and diabetes. [ ]

Although prior studies have confirmed the importance of dietary intervention in managing GDM, several limitations remain in the current literature. First, most existing interventions rely on generalized dietary guidance without tailoring to the cognitive load or psychological readiness of pregnant women, which may affect adherence and effectiveness. Second, many studies lack integration with validated behavioral change models such as the TTM, resulting in less personalized and stage-specific intervention strategies. Third, outcome evaluations often focus solely on glycemic control, while neglecting critical psychological factors such as self-efficacy and self-management ability, which are known to influence long-term behavioral outcomes.

Furthermore, few studies apply structured, multiphase dietary education programs within routine clinical settings using standardized frameworks and matched comparison groups. Therefore, there remains a need for research that not only incorporates cognitive and psychological theory into dietary interventions, but also evaluates their association with both metabolic and psychosocial outcomes in women with GDM.

However, there are relatively few clinical studies on the application of cognitive load-based education based on the TTM in pregnant women with GDM. Therefore, this study aims to systematically examine the association between this educational approach and clinical outcomes in women with GDM. It also seeks to conduct an in-depth analysis of the changes in various indicators after intervention, providing more scientific and effective educational strategies for clinical practice.

2. Materials and methods

### 2.1. General information

This study was approved by the Ethics Committee of Nantong University Affiliated Maternal and Child Health Hospital. The approval number is NTFY-2021-092, and the date of approval was August 25, 2021. A retrospective analysis was conducted on the clinical data of 126 pregnant women with GDM admitted to our hospital from September 2021 to September 2023. According to different nursing interventions, they were divided into a control group and an observation group. The control group was given conventional interventions, while the observation group was given cognitive load-based dietary education based on the TTM in addition to the conventional interventions. General information such as age, education level, type of delivery, history of GDM, gestational age, body mass index (BMI), place of residence, family history of diabetes, and monthly household income was collected. This study was submitted to and approved by the Ethics Committee of our hospital.

### 2.2. Inclusion and exclusion criteria

Inclusion criteria:

- patients who met the GDM diagnostic criteria in the Guidelines for the Diagnosis and Treatment of Diabetes Mellitus during Pregnancy (2014), [ ] with fasting blood glucose ≥5.8 mmol/L confirmed by 2 oral glucose tolerance tests;

- age >18 years and singleton pregnancy;

- intrauterine pregnancy;

- normal glucose metabolism before pregnancy;

- no use of hypoglycemic drugs or glycemic control interventions;

- no other pregnancy-related complications and unrestricted limb movements;

- clear consciousness, normal communication ability, and compliance with treatment;

- informed consent obtained from pregnant women and their families after being informed of the study content, with signed consent forms.

Exclusion criteria:

- combined dysfunction of organs such as liver and kidney;

- presence of cognitive impairment, mental disorders, or recent history of antipsychotic medication use;

- combined acute or chronic infectious diseases such as pneumonia and tuberculosis;

- combined immune dysfunction or malignant tumors;

- combined diabetic ketoacidosis;

- missing medical records.

### 2.3. Nursing methods

The control group was given conventional interventions, while the observation group was given cognitive load-based dietary education based on the TTM in addition to the conventional interventions. The intervention period lasted until after delivery. The specific measures were as follows.

#### 2.3.1. Conventional interventions

- Health education: Distribute GDM prevention and control manuals and explain GDM-related knowledge in detail to pregnant women and their families, including the pathogenesis, risk factors, hazards, and prevention of GDM, based on clinical experience. Pregnant women were invited to follow the department’s official WeChat account and join the pregnancy WeChat group. Every Wednesday, an article or video related to pregnancy was posted on the official account and in the group.

- Psychological counseling: Share successful delivery cases of GDM patients in the hospital with pregnant women and their families to alleviate psychological pressure and negative emotions, improve psychological status, and enhance treatment compliance.

- Blood glucose monitoring: Instruct pregnant women and their families to scientifically and regularly monitor blood glucose levels and changes. For those with poor glycemic control, hypoglycemic drugs should be administered as early as possible according to medical advice.

- Medication guidance: Provide detailed information to pregnant women and their families regarding the usage, dosage, and precautions of hypoglycemic drugs, and instruct family members to supervise the correct medication according to medical advice.

- Dietary intervention: Provide scientific dietary guidance based on dietary structure, calorie intake, and meal frequency. Recommend 6 meals a day, ensuring the intake of low-sugar, low-fat, high-protein, high-fiber foods, and trace elements, and avoiding spicy foods. Reasonably control the calorie intake for breakfast, lunch, and dinner. During the second and third trimesters of pregnancy, pay attention to changes in the BMI of pregnant women and adjust the daily diet to ensure appropriate calorie intake in a timely manner.

- Exercise intervention: Based on the physical condition and exercise habits of pregnant women, guide them to take proper walks and add other exercises such as climbing stairs and pregnancy gymnastics. Exercise should be done 1 hour after meals, 30 minutes per session, 3 times a day. In the second trimester, climbing stairs can be appropriately increased to 10 minutes per session, 2 times a day. In the third trimester, avoid intense activities and choose activities such as walking and upper limb exercises, 20 minutes per session, 3 times a day.

- Complication monitoring and rehabilitation guidance: Instruct pregnant women and their families to regularly monitor blood glucose and blood pressure levels, closely monitor weight changes, and adjust diet and exercise habits in a timely manner. Pay attention to preventing complications such as diabetic ketoacidosis and hyperosmolar coma, and inform nursing staff promptly in case of special situations. After discharge, strictly follow the rehabilitation guidance and conduct regular telephone follow-ups. For related problems, pregnant women can contact WeChat group administrators online for consultation (Table ).

#### 2.3.2. Cognitive load-based dietary education based on the TTM

- Establishment of a cognitive load-based dietary education team: ① Team composition: The team consisted of 1 obstetrician, 1 head nurse, 5 nurses with more than 5 years of obstetric experience, and 1 nutritionist. The head nurse served as the team leader, responsible for summarizing and collecting data as well as assisting in the formulation and supervision of the intervention plan. ② Training meeting: A training meeting on cognitive load-based dietary education based on TTM was organized. The intervention plan was discussed, studied, and refined during the meeting. After the meeting, a unified assessment was conducted to ensure that team members were proficient in the intervention plan and its application.

- ① Team composition: The team consisted of 1 obstetrician, 1 head nurse, 5 nurses with more than 5 years of obstetric experience, and 1 nutritionist. The head nurse served as the team leader, responsible for summarizing and collecting data as well as assisting in the formulation and supervision of the intervention plan.

- ② Training meeting: A training meeting on cognitive load-based dietary education based on TTM was organized. The intervention plan was discussed, studied, and refined during the meeting. After the meeting, a unified assessment was conducted to ensure that team members were proficient in the intervention plan and its application.

- Precontemplation stage: ① Assessment: The psychological and cognitive load levels of pregnant women were assessed using the Psychological Load Scale and Mental Effort Scale. Based on the assessment results, pregnant women were divided into Group A (score < 3) and Group B (score ≥ 3). ② Targeted education: Focused education was provided to pregnant women in both groups who had unhealthy eating habits, poor physical fitness, or low awareness of GDM and willingness for self-management. GDM-related knowledge, including causes, risk factors, and short- and long-term hazards of GDM, was disseminated using brochures and educational videos. Detailed explanations were given about dietary intake and energy consumption standards for 3 meals a day to raise awareness of healthy eating among pregnant women and their families. ③ Case sharing: Both positive and negative cases of GDM pregnant women were shared to illustrate the adverse impacts of GDM. This approach aimed to help pregnant women recognize their high-risk factors and conditions, thereby raising their crisis awareness, enhancing their willingness to participate, and boosting their self-management awareness and confidence in recovery.

- ① Assessment: The psychological and cognitive load levels of pregnant women were assessed using the Psychological Load Scale and Mental Effort Scale. Based on the assessment results, pregnant women were divided into Group A (score < 3) and Group B (score ≥ 3).

- ② Targeted education: Focused education was provided to pregnant women in both groups who had unhealthy eating habits, poor physical fitness, or low awareness of GDM and willingness for self-management. GDM-related knowledge, including causes, risk factors, and short- and long-term hazards of GDM, was disseminated using brochures and educational videos. Detailed explanations were given about dietary intake and energy consumption standards for 3 meals a day to raise awareness of healthy eating among pregnant women and their families.

- ③ Case sharing: Both positive and negative cases of GDM pregnant women were shared to illustrate the adverse impacts of GDM. This approach aimed to help pregnant women recognize their high-risk factors and conditions, thereby raising their crisis awareness, enhancing their willingness to participate, and boosting their self-management awareness and confidence in recovery.

- Contemplation stage: ① Assessment: The dietary habits, exercise habits, and lifestyle of pregnant women were assessed to understand their willingness for dietary and exercise management during pregnancy. Knowledge about the impact of dietary habits and lifestyle on weight gain, blood glucose control, and the risk of GDM was imparted to guide them to express their thoughts and concerns actively. Pregnant women were encouraged to share their current unhealthy dietary and exercise habits and were assisted in analyzing and discussing solutions to gradually enhance their willingness for recovery. ② Educational lectures: Educational lectures were organized to strengthen crisis awareness among pregnant women. A WeChat group for pregnant women was set up, with pregnancy-related health knowledge shared every Wednesday and real-time Q&A provided in the group.

- ① Assessment: The dietary habits, exercise habits, and lifestyle of pregnant women were assessed to understand their willingness for dietary and exercise management during pregnancy. Knowledge about the impact of dietary habits and lifestyle on weight gain, blood glucose control, and the risk of GDM was imparted to guide them to express their thoughts and concerns actively. Pregnant women were encouraged to share their current unhealthy dietary and exercise habits and were assisted in analyzing and discussing solutions to gradually enhance their willingness for recovery.

- ② Educational lectures: Educational lectures were organized to strengthen crisis awareness among pregnant women. A WeChat group for pregnant women was set up, with pregnancy-related health knowledge shared every Wednesday and real-time Q&A provided in the group.

- Preparation stage: Group A: Through brochures and videos, detailed explanations were provided to pregnant women and their families on the relationship between daily dietary intake and energy consumption, focusing on the practical application of the food exchange method. They were assisted in formulating scientific dietary plans to ensure balanced daily energy intake and consumption. Group B: The importance of a scientific diet for GDM, dietary precautions, and requirements for a balanced diet were introduced. Specific meal examples were provided, and personalized dietary and exercise plans were developed based on nutritional needs. Distribution of health manuals: Health manuals were distributed to reinforce knowledge. Calorie intake was reasonably controlled according to BMI, with the proportion of protein, fat, and carbohydrates set at 20:25:55, and the energy intake for breakfast, lunch, and dinner set at 25%, 40%, and 35%, respectively. The intake of whole grains, high-calcium milk, fresh fruits, and vegetables was increased, along with appropriate supplementation of vitamins and trace elements. Exercise education: The importance of exercise during pregnancy was emphasized. For gestational age ≤27 weeks, aerobic exercises such as walking and prenatal yoga were recommended, with attention to duration and intensity: 50 minutes per session, once a day. For gestational age >27 weeks, postprandial walking was recommended as the main form of exercise: 30 minutes per session. Implementation: Blood glucose monitoring was strictly implemented, with regular checks on urinary ketone levels and liver and kidney functions to track fetal development.

- Group A: Through brochures and videos, detailed explanations were provided to pregnant women and their families on the relationship between daily dietary intake and energy consumption, focusing on the practical application of the food exchange method. They were assisted in formulating scientific dietary plans to ensure balanced daily energy intake and consumption.

- Group B: The importance of a scientific diet for GDM, dietary precautions, and requirements for a balanced diet were introduced. Specific meal examples were provided, and personalized dietary and exercise plans were developed based on nutritional needs.

- Distribution of health manuals: Health manuals were distributed to reinforce knowledge. Calorie intake was reasonably controlled according to BMI, with the proportion of protein, fat, and carbohydrates set at 20:25:55, and the energy intake for breakfast, lunch, and dinner set at 25%, 40%, and 35%, respectively. The intake of whole grains, high-calcium milk, fresh fruits, and vegetables was increased, along with appropriate supplementation of vitamins and trace elements.

- Exercise education: The importance of exercise during pregnancy was emphasized. For gestational age ≤27 weeks, aerobic exercises such as walking and prenatal yoga were recommended, with attention to duration and intensity: 50 minutes per session, once a day. For gestational age >27 weeks, postprandial walking was recommended as the main form of exercise: 30 minutes per session.

- Implementation: Blood glucose monitoring was strictly implemented, with regular checks on urinary ketone levels and liver and kidney functions to track fetal development.

- Action stage: Monthly online meetings: A video conference for pregnant women was held once a month, with experts and nurses invited to participate. The dietary structure and psychological status of pregnant women were reviewed, encouraging them to express their needs actively and share their experiences. Problem solving: Based on the dietary and exercise records and changes in body weight and blood glucose levels, the team discussed existing problems in the current plan with pregnant women and worked out solutions together. Family members were instructed to supervise pregnant women in following the plan.

- Monthly online meetings: A video conference for pregnant women was held once a month, with experts and nurses invited to participate. The dietary structure and psychological status of pregnant women were reviewed, encouraging them to express their needs actively and share their experiences.

- Problem solving: Based on the dietary and exercise records and changes in body weight and blood glucose levels, the team discussed existing problems in the current plan with pregnant women and worked out solutions together. Family members were instructed to supervise pregnant women in following the plan.

- Maintenance stage: In-hospital promotion: Prominent slogans and posters were displayed in the hospital to strengthen in-hospital dietary education and promotion. Telephone follow-ups: Telephone follow-ups were conducted to monitor blood glucose levels, body weight changes, and the implementation of dietary and exercise plans in pregnant women. Encouragement and support were provided, relevant questions were answered, and family members were instructed to supervise and motivate pregnant women to prevent behavioral relapse. Follow-ups were conducted once every 2 weeks.

- In-hospital promotion: Prominent slogans and posters were displayed in the hospital to strengthen in-hospital dietary education and promotion.

- Telephone follow-ups: Telephone follow-ups were conducted to monitor blood glucose levels, body weight changes, and the implementation of dietary and exercise plans in pregnant women. Encouragement and support were provided, relevant questions were answered, and family members were instructed to supervise and motivate pregnant women to prevent behavioral relapse. Follow-ups were conducted once every 2 weeks.

### 2.4. Observation indicators

Data were collected from the medical record system, including blood glucose levels, urinary ketone levels, GDM self-management ability, self-efficacy, and the incidence of adverse pregnancy outcomes.

- Blood glucose levels and urinary ketone levels: Fasting plasma glucose (FPG), 2-hour postprandial glucose (2hPG), and urinary ketone levels were measured the day before and the day after the intervention. Testing methods: ① Blood glucose: In the early morning, 5 mL of fasting venous blood was collected from pregnant women and left at room temperature for 20 minutes. The supernatant (3 mL) was separated by centrifugation at 3000 r/min for 10 minutes using the Beckman Coulter automated biochemical analyzer (Model: Au5800, Guangzhou Aolong Biotechnology Co., Ltd.) and stored at −80°C for testing. FPG and 2hPG levels were measured using the Mindray automated biochemical analyzer (Model: BS-350S, Wuhan Aliru Medical Equipment Co., Ltd.). ② Urinary ketones: Midstream morning urine samples were collected from pregnant women and analyzed for urinary ketone levels using an automated urine analyzer (Model: Mindray OPM-1560A, Nanjing Baiden Medical Co., Ltd.). Normal ranges: FPG: 3.9 to 6.1 mmol/L; 2hPG: 4.4 to 7.8 mmol/L; urinary ketones: 2.0 to 4.0 mg/L.

- ① Blood glucose: In the early morning, 5 mL of fasting venous blood was collected from pregnant women and left at room temperature for 20 minutes. The supernatant (3 mL) was separated by centrifugation at 3000 r/min for 10 minutes using the Beckman Coulter automated biochemical analyzer (Model: Au5800, Guangzhou Aolong Biotechnology Co., Ltd.) and stored at −80°C for testing. FPG and 2hPG levels were measured using the Mindray automated biochemical analyzer (Model: BS-350S, Wuhan Aliru Medical Equipment Co., Ltd.). ② Urinary ketones: Midstream morning urine samples were collected from pregnant women and analyzed for urinary ketone levels using an automated urine analyzer (Model: Mindray OPM-1560A, Nanjing Baiden Medical Co., Ltd.). Normal ranges: FPG: 3.9 to 6.1 mmol/L; 2hPG: 4.4 to 7.8 mmol/L; urinary ketones: 2.0 to 4.0 mg/L.

- Self-management ability: Self-management ability was assessed the day before and the day after the intervention using the Self-Management Ability Scale (SMAS). [ ] This scale consists of 26 items across 4 dimensions, including GDM-related knowledge, beliefs, and attitudes. Each item is scored from 1 to 5. Strongly disagree: 1 point; strongly agree: 5 points. Total score: 26 to 130 points, with higher scores indicating better self-management ability. The overall Cronbach alpha of the scale was 0.937, indicating good reliability and validity.

- Self-efficacy: Self-efficacy was assessed the day before and the day after the intervention using the General Self-Efficacy Scale (GSES). [ ] This scale consists of 10 items, each scored from 1 to 4. Somewhat true: 2 points; completely true: 4 points. Total score: 40 points, with higher scores indicating greater self-efficacy. The overall Cronbach alpha of the scale was 0.922, indicating good reliability and validity.

- Adverse pregnancy outcomes: Based on previous medical records, the incidence of adverse pregnancy outcomes, including macrosomia/congenital malformations, premature rupture of membranes, amniotic fluid abnormalities, neonatal death, and postpartum hemorrhage, was collected.

The SMAS focuses on specific GDM-related behaviors across 4 dimensions: knowledge, beliefs and attitudes, behavioral implementation, and social support. It evaluates participants’ concrete self-management practices tailored to GDM care. In contrast, the GSES is a general psychological measure that assesses a person’s perceived confidence in managing challenges across various contexts. It reflects participants’ overall psychological readiness and belief in their ability to execute health-related behaviors, regardless of disease specificity. Although both scales involve self-regulation constructs, their measurement dimensions do not substantially overlap. The SMAS is behavior-oriented and GDM-specific, while the GSES captures general self-efficacy as a cognitive-emotional trait. The dual use of these tools provides a more nuanced understanding of both domain-specific behavioral competencies and global psychological resilience among pregnant women with GDM.

### 2.5. Statistical methods

IBM SPSS Statistics for Windows, version 27.0 (IBM Corp., Armonk) was used to analyze the data. Count data were expressed as [n]. If the sample size was ≥40 and the theoretical frequency T ≥ 5, the basic formula of the chi-square test was used, and the test statistic was χ 2 ; if the sample size was ≥40 but the theoretical frequency 1 ≤ T < 5, the corrected formula of the chi-square test was used; if the sample size was < 40 or the theoretical frequency T < 1, Fisher exact probability method was used for statistical analysis. Measurement data were first tested by the Shapiro–Wilk method to determine whether they conformed to a normal distribution. Measurement data conforming to a normal distribution were expressed as ( x ¯ ± s ) and analyzed by the t -test; measurement data not conforming to a normal distribution were expressed as median and interquartile range [ M (P25, P75)] and analyzed by nonparametric tests. A P -value <.05 was considered statistically significant. The propensity score matching method was used to match the control group and the observation group at a ratio of 1:1, with a caliper value of 0.02. The intervention method for pregnant women was set as the dependent variable, and 9 confounding factors including age, education level, type of delivery, history of GDM, gestational age, BMI, place of residence, family history of diabetes, and monthly household income were set as covariates. Propensity scores were calculated by logistic regression analysis.

3. Results

### 3.1. Comparison of general information between the 2 groups

Before matching, there were differences between the 2 groups of pregnant women in terms of gestational age, type of delivery, education level, and family history of diabetes ( P < .05). After matching, the general information such as age, education level, type of delivery, history of GDM, gestational age, BMI, place of residence, family history of diabetes, and monthly household income was basically the same between the 2 groups ( P > .05), making them comparable. See Table .

### 3.2. Comparison of blood glucose levels and urinary ketone levels

Before the intervention, there were no significant differences in FPG, 2hPG, and urinary ketone levels between the 2 groups of pregnant women ( P > .05). After the intervention, the levels of FPG, 2hPG, and urinary ketones in the observation group were lower than those in the control group ( P < .05). See Table .

### 3.3. Comparison of self-management ability

Before the intervention, there were no significant differences between the 2 groups of pregnant women in terms of beliefs and attitudes, GDM-related knowledge, self-management methods and behaviors, social support, and total self-management ability scores ( P > .05). After the intervention, the scores of each dimension in the observation group were higher than those in the control group ( P < .05). See Table .

### 3.4. Comparison of self-efficacy scores

Before the intervention, there was no significant difference in self-efficacy scores between the 2 groups of pregnant women ( P > .05). After the intervention, the self-efficacy scores of the observation group were higher than those of the control group ( P < .05). See Table .

### 3.5. Comparison of incidence of adverse pregnancy outcomes

As shown in Table , the overall incidence of adverse pregnancy outcomes was significantly lower in the observation group compared to the control group (11.90% vs 30.95%, χ 2 = 4.525, P = .033). In the control group, 13 adverse events occurred, including cases of macrosomia or congenital malformations (n = 4), premature rupture of membranes (n = 2), amniotic fluid abnormalities (n = 3), neonatal death (n = 1), and postpartum hemorrhage (n = 3). In the observation group, only 5 adverse events were recorded, with no neonatal deaths and fewer occurrences across all categories. While individual complications were not analyzed for statistical significance due to small numbers, the total incidence showed a notable difference, suggesting a positive association between the dietary education intervention and pregnancy outcomes.

4. Discussion

GDM is a common disease during pregnancy, influenced by various factors such as genetics and obesity, leading to abnormal glucose tolerance in pregnant women. [ ] Although most pregnant women can return to normal glucose metabolism after delivery, up to 50% of them develop type 2 diabetes postpartum. Moreover, GDM can cause abnormal embryonic development, posing a serious threat to the physical and mental health as well as the safety of both mother and child. [ , ] Previous studies have confirmed [ ] that most pregnant women with GDM can achieve satisfactory glycemic control through dietary management alone. However, due to issues such as poor dietary habits, inadequate health awareness, and low compliance, the glycemic control effect in pregnant women with GDM is often unsatisfactory, leading to an increased risk of adverse pregnancy outcomes. Therefore, adopting scientifically effective dietary education is of great significance for stabilizing blood glucose levels in pregnant women with GDM, enhancing self-management awareness, and improving maternal and neonatal outcomes.

This study found that after the intervention, the levels of FPG, 2hPG, and urinary ketones in the observation group were lower than those in the control group, and the incidence of adverse pregnancy outcomes in the observation group was also lower than that in the control group ( P < .05). These results suggest that cognitive load-based dietary education based on the TTM was associated with lower blood glucose and urinary ketone levels in pregnant women with GDM and may be linked to better pregnancy outcomes.

A large number of studies have shown [ – ] that blood glucose control levels in pregnant women with GDM are closely related to adverse pregnancy outcomes. Pregnant women with higher blood glucose levels have an increased risk of adverse events such as amniotic fluid abnormalities, premature rupture of membranes, neonatal asphyxia, and adverse perinatal outcomes. A study by Zhang et al [ ] found that some pregnant women with GDM continued to exhibit high levels of positive urinary ketones even after achieving target blood glucose control. Prolonged exposure to high levels of ketones can easily cause abnormal embryonic development and increase the probability of adverse pregnancy outcomes. Research by Song [ ] suggested that helping pregnant women with GDM to learn about healthy dietary knowledge and master the application and techniques of the food exchange method can promote adherence to dietary control, stabilize blood glucose levels, and thereby improve delivery outcomes. As a key measure for controlling blood glucose levels in pregnant women with GDM, dietary intervention in the observation group of this study involved cognitive load-based dietary education based on the TTM. This approach was designed based on the cognitive characteristics and psychological load levels of pregnant women with GDM, employing a 5-stage dynamic intervention process (precontemplation, contemplation, preparation, action, and maintenance) to address their health dietary needs and motivations. Through this approach, pregnant women with GDM were able to understand and master relevant knowledge such as energy conversion and daily carbohydrate intake. This effectively stimulated positive changes in their dietary structure and lifestyle habits, helping them to form long-term, stable, scientific dietary habits and healthy exercise patterns, which in turn improved blood glucose levels and reduced the occurrence of positive urinary ketones.

Moreover, strengthening maternal and fetal monitoring and closely observing fetal development can effectively reduce the risk of pregnancy complications in pregnant women with GDM, playing a positive role in improving pregnancy outcomes.

This study found that the dietary education was associated with higher scores across all dimensions of self-management ability in the observation group than those in the control group ( P < .05), suggesting that cognitive load-based dietary education based on the TTM may be associated with improved self-management ability in pregnant women with GDM. A retrospective study conducted by Bouclaous et al [ ] found that low education level is a risk factor affecting self-management and care in diabetic patients, who are at a higher risk of developing type 2 diabetes and tend to perform poorly in adopting healthy habits such as diet and exercise. Wu et al [ ] reported that pregnant women with GDM often experience psychological stress due to concerns about their own and their fetus’s health, which can exacerbate the secretion of stress hormones and worsen the condition of GDM. Personalized dietary education for pregnant women with different cognitive levels, with well-integrated teaching content and reasonable allocation, can prevent cognitive overload. As GDM pregnant women improve their health knowledge, their self-management ability is also enhanced. In this study, the observation group received cognitive load-based dietary education based on the TTM. During the precontemplation stage, the psychological load and cognitive levels of pregnant women with GDM were assessed to understand their willingness for recovery and psychological status. Then, targeted dietary education was carried out according to their cognitive characteristics and psychological load levels. The reasonable allocation of teaching content helped prevent cognitive overload, ensured the effectiveness of education, and at the same time stimulated self-management awareness and confidence in recovery among pregnant women with GDM, thereby enhancing their self-management ability. Furthermore, the combined use of a disease-specific SMAS and a GSES allowed for a more comprehensive assessment of both practical behavioral competencies and psychological confidence among women with GDM. While SMAS focuses on GDM-specific management behaviors such as diet, monitoring, and support, GSES captures an individual’s broader confidence in coping with health-related challenges. This multidimensional evaluation is essential for tailoring educational interventions and understanding the interplay between psychological readiness and behavioral execution in chronic disease self-care.

This study found that after the intervention, the self-efficacy scores of the observation group were higher than those of the control group ( P < .05), suggesting that cognitive load-based dietary education based on the TTM was linked to higher self-efficacy in pregnant women with GDM. This finding is consistent with the results of a study by Zou et al. [ ] A randomized clinical trial conducted by Rostampour et al [ ] also demonstrated that continuous communication, understanding the psychological status and health behavior needs of pregnant women with GDM, and providing targeted interventions can effectively improve self-efficacy in this population. In this study, the observation group received cognitive load-based dietary education based on the TTM. The education plan was dynamically designed and individualized according to the cognitive ability and psychological load level assessment results of pregnant women with GDM, as well as the changing needs of pregnant women at different stages. Along with the synchronized participation of family members in supervising the health behaviors of pregnant women with GDM, positive reinforcement and encouragement were provided. This approach guided pregnant women with GDM to communicate actively, express their inner needs and concerns, and assisted them in analyzing and solving problems. Such measures were effective in improving their cognitive levels, reducing psychological stress, and enhancing confidence in adopting healthy behaviors, thereby significantly boosting self-efficacy in pregnant women with GDM.

Despite the encouraging findings, several limitations of this study must be acknowledged. First, as a retrospective observational study, there is potential for measurement bias and information bias due to reliance on existing medical records and self-reported data. Although we used propensity score matching to control for known confounding variables, residual confounding from unmeasured or unknown factors cannot be completely ruled out. Second, while the intervention was implemented by a team including trained obstetric nurses and a nutritionist, we did not explicitly standardize all components of the education content or formally assess inter-provider consistency across all participants. This may have introduced variability in intervention delivery, which could influence the internal consistency and external validity of the findings. In future studies, a prospective randomized controlled trial design with blinded outcome assessment, standardized intervention protocols, and implementation fidelity assessments would strengthen the validity of conclusions and enhance reproducibility. Additionally, incorporating objective digital tracking or structured interview tools could reduce information bias and provide more precise outcome measurements.

In conclusion, the application of cognitive load-based dietary education based on the TTM in pregnant women with GDM can help improve their self-management ability, enhance self-efficacy, and may support better glycemic control and favorable pregnancy outcomes. This educational model may offer a practical strategy to inform clinical practice. However, this study only selected pregnant women with GDM admitted to our hospital during a specific period, with relatively limited intervention time and sample size. In the future, large-sample, multicenter randomized controlled trials with extended follow-up periods are needed to evaluate the long-term effects of this intervention strategy.

Author contributions

Conceptualization: Hongxia Cao, Yingchun Wu.

Data curation: Hongxia Cao, Yingchun Wu.

Formal analysis: Hongxia Cao, Yingchun Wu.

Investigation: Yingchun Wu.

Methodology: Yingchun Wu.

Visualization: Yingchun Wu.

Writing – original draft: Hongxia Cao, Yingchun Wu.

Writing – review & editing: Hongxia Cao, Yingchun Wu.