Preconception Dietary Inflammatory Index and Risk of Gestational Diabetes Mellitus Based on Maternal Body Mass Index: Findings from a Japanese Birth Cohort Study

Association between Preconception Dietary Fiber Intake and Preterm Birth: The Japan Environment and Children's Study

Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. Therefore, this study aimed to determine whether preconception dietary fiber intake is associated with PTB. This was a prospective cohort Japan Environmental and Children's Study (JECS). The study population comprised 85,116 singleton live-birth pregnancies from the JECS database delivered between 2011 and 2014. The participants were categorized into five groups based on their preconception dietary fiber intake quintiles (Q1 and Q5 were the lowest and highest groups, respectively). Multiple logistic regression analysis was performed to determine the association between preconception dietary fiber intake and PTB. Multiple logistic regression analysis revealed that the risk for PTB before 34 weeks was lower in the Q3, Q4, and Q5 groups than in the Q1 group (Q3: adjusted odds ratio [aOR] 0.78, 95% confidence interval [CI] 0.62-0.997; Q4: aOR 0.74, 95% CI 0.57-0.95; Q5: aOR 0.68, 95% CI 0.50-0.92). However, there was no significant difference between preconception dietary fiber intake and PTB before 37 weeks. In conclusion, higher preconception dietary fiber intake correlated with a reduced the risk for PTB before 34 weeks. Therefore, new recommendations on dietary fiber intake as part of preconception care should be considered.

Preconception Stress and Pregnancy Serum Glucose Levels Among Women Attending a Fertility Center

Context

The association between women's stress and pregnancy glucose levels remain unclear, specifically when considering the preconception period as a sensitive window of exposure.

Objective

We investigated whether preconception perceived stress was associated with glucose levels during pregnancy among women attending a fertility center (2004-2019).

Methods

Before conception, women completed a psychological stress survey using the short version of the validated Perceived Stress Scale 4 (PSS-4), and blood glucose was measured using a 50-gram glucose load test during late pregnancy as a part of screening for gestational diabetes. Linear and log-binomial regression models were used to assess associations of total PSS-4 scores with mean glucose levels and abnormal glucose levels ( ≥ 140 mg/dL), adjusting for age, body mass index, race, smoking, education, physical activity, primary infertility diagnosis, number of babies, and mode of conception.

Results

Psychological stress was positively associated with mean abnormal glucose levels. The adjusted marginal means (95% CI) of mean glucose levels for women in the first, second, and third tertiles of psychological stress were 115 (110, 119), 119 (115, 123), and 124 (119, 128), and mg/dL, respectively (P for trend = .007). Also, women in the second and third tertiles of psychological stress had 4% and 13% higher probabilities of having abnormal glucose compared with women in the first tertile of psychological stress (P trend = .01).

Conclusion

These results highlight the importance of considering preconception when evaluating the relationship between women's stress and pregnancy glucose levels.

Association between plant-based or animal-based dietary pattern and plasma glucose during oral glucose tolerance test among Chinese women with gestational diabetes mellitus: a prospective cohort study

OBJECTIVE

This study explored whether plant-based and animal-based dietary patterns are associated with plasma glucose levels during oral glucose tolerance test in women with gestational diabetes mellitus (GDM).

DESIGN

A prospective cohort study was conducted using a Food Frequency Questionnaire to collect dietary data. Dietary patterns were derived using principal component analysis. Multivariate logistic regression analysis was performed to explore the association between dietary patterns and plasma glucose levels. Stratified analyses were conducted according to maternal age, prepregnancy body mass index (BMI) and other confounders.

SETTING AND PARTICIPANTS

The study, conducted in January 2022 in two hospitals in Fujian, China, involved 424 women diagnosed with GDM using a 75 g 2-hour oral glucose tolerance test at 24-28 gestational weeks.

RESULTS

Six maternal dietary patterns (plant based and animal based) were identified. Participants with plant-based pattern had lower 2-hour plasma glucose levels than those with animal-based pattern (β=-0.314; 95% CI (-0.596 to -0.032)). After adjusting the regression model covariates, this significant association remained (β=-0.288; 95% CI (-0.568 to -0.008)) and appeared more pronounced in women aged 30 years or above and those with prepregnancy BMI<24 kg/m2.

CONCLUSIONS

Plant-based pattern is associated with lower plasma glucose levels in women with GDM, which is valuable information for dietary counselling and intervention.

The association between the dietary inflammatory index and gestational diabetes mellitus: A systematic review of observational studies

BACKGROUND & AIMS

Unhealthy dietary habits contribute to low-grade chronic inflammation that is known to be associated with metabolic disorders and pregnancy complications such as gestational diabetes mellitus (GDM). The dietary inflammatory index (DII) is a scoring system for assessing the inflammatory potential of various nutrients and foods. This systematic review aims to investigate the current state of evidence on the association between DII and GDM in pregnant women.

METHODS

PubMed, Scopus and Web of Science electronic databases were systematically searched for relevant English-language articles published up to February 2023. This study was developed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (CRD42022382813).

RESULTS

This review included seven studies (98,115 participants) from five countries. In total, two case-control studies have shown a positive association between DII and GDM. In contrast, three of five cohort studies found no association between dietary inflammatory potential and the risk of developing GDM.

CONCLUSION

We found some controversial results due to the small number of studies, with major heterogeneity in research design and findings. Collectively, the current study does not support an association between the DII score and the risk of gestational diabetes. Further, longitudinal studies are needed to elucidate the association between dietary inflammatory potential and GDM.

Association between Gestational Weight Gain and Risk of Hypertensive Disorders of Pregnancy among Women with Obesity: A Multicenter Retrospective Cohort Study in Japan

The relationship between weight gain during pregnancy and the onset of hypertensive disorders of pregnancy in women with pre-pregnancy obesity remains unclear. We examined the effects of weight gain during pregnancy on hypertensive disorders of pregnancy among women with pre-pregnancy body mass index (BMI) ≥ 25.0 kg/m². This multicenter retrospective cohort study included nullipara women who delivered at two units in Japan between 1 January 2013, and 31 December 2020. Singleton primipara (n = 3040) were categorized into two pre-pregnancy BMI groups: 25.0-<30.0, and ≥30.0 kg/m². Using multiple logistic regression analyses (reported as adjusted odds ratio and 95% confidence interval), gestational weight gain effects on overall hypertensive disorders of pregnancy, gestational hypertension, and pre-eclampsia were determined. Gestational weight gain increased hypertensive disorders of pregnancy (1.09, 1.03-1.16, p < 0.05) and pre-eclampsia risk (1.10, 1.01-1.20, p < 0.05) among the BMI 25.0-<30.0 kg/m² group and hypertensive disorders of pregnancy risk among the ≥30.0 kg/m² group (1.07, 1.00-1.05, p < 0.05). Using receiver operating characteristic curve analyses, among the BMI 25.0-<30.0 kg/m² group, for hypertensive disorders of pregnancy (area under the curve [AUC], 0.63, p < 0.05) and pre-eclampsia (AUC, 0.62; p < 0.05), the weight gain cut-off was 10.5 and 10.6 kg, with sensitivity/specificity of 0.47/0.73 and 0.50/0.73, respectively. For the BMI ≥30.0 kg/m² group (AUC, 0.63, p < 0.05), the cut-off was 3.5 kg (sensitivity/specificity, 0.75/0.49). The optimal gestational weight gain for reducing hypertensive disorders of pregnancy among women with a pre-pregnancy BMI > 25 kg/m² may facilitate personalized pre-conception counseling among women with obesity.

The effect of diet quality on the risk of developing gestational diabetes mellitus: A systematic review and meta-analysis

Objective

To examine the effect of diet quality on the risk of gestational diabetes mellitus.

Methods

This review included cohort and case-control studies reporting an association between diet quality and gestational diabetes mellitus. We searched PubMed, Cochrane Library, Web of Science, Embase, PsycINFO, CINAHL Complete, Chinese Periodical Full-text Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and China Wanfang Database for studies published from inception to November 18, 2022. The Newcastle-Ottawa Scale was used for quality assessment, and the overall quality of evidence was assessed using the GRADEpro GDT.

Results

A total of 19 studies (15 cohort, four case-control) with 108,084 participants were included. We found that better higher diet quality before or during pregnancy reduced the risk of developing gestational diabetes mellitus, including a higher Mediterranean diet (OR: 0.51; 95% CI: 0.30-0.86), dietary approaches to stop hypertension (OR: 0.66; 95% CI: 0.44-0.97), Alternate Healthy Eating Index (OR: 0.61; 95% CI: 0.44-0.83), overall plant-based diet index (OR: 0.57; 95% CI: 0.41-0.78), and adherence to national dietary guidelines (OR: 0.39; 95% CI:0.31-0.48). However, poorer diet quality increased the risk of gestational diabetes mellitus, including a higher dietary inflammatory index (OR: 1.37; 95% CI: 1.21-1.57) and overall low-carbohydrate diets (OR: 1.41; 95% CI: 1.22-1.64). After meta-regression, subgroup, and sensitivity analyses, the results remained statistically significant.

Conclusions

Before and during pregnancy, higher diet quality reduced the risk of developing gestational diabetes mellitus, whereas poorer diet quality increased this risk.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022372488.