Adverse obstetric outcomes in early-diagnosed gestational diabetes mellitus: The Japan Environment and Children's Study

Glucose variability as a key mediator in the relationship between pre-pregnancy overweight/obesity and late-onset hypertensive disorders of pregnancy

To evaluate the role of high glucose variability (High-GV) in early pregnancy as a potential mediating factor between pre-pregnancy overweight/obesity and late-onset HDP (LoHDP), where effective preventive strategies remain limited. This multicenter retrospective study analyzed data from 802 pregnancies across 14 facilities. Pregnancies with a 75 g-OGTT performed by 20 weeks of gestation were included. Structural equation modeling (SEM) was used to evaluate direct and indirect effects of body mass index (BMI), High-GV, and covariates (e.g., age, ART, primiparity) on LoHDP. Overweight/obese women had significantly higher rates of High-GV (26.1 vs. 16.4%, p = 0.001) and LoHDP (17.6 vs. 7.9%, p < 0.001) compared to non-overweight/obese women. SEM revealed that BMI influenced LoHDP through both direct and indirect pathways. BMI had a direct effect on LoHDP (β = 0.20, p < 0.01), and an indirect effect mediated by High-GV, with BMI significantly associated with High-GV (β = 0.15, p < 0.01), and High-GV positively associated with LoHDP (β = 0.12, p < 0.01). In Non-GDM pregnancies, High-GV showed an even stronger association with LoHDP (β = 0.25, p < 0.001). This study identifies High-GV as a key mediator linking pre-pregnancy overweight/obesity to LoHDP. These findings suggest that targeting glucose variability in early pregnancy could mitigate LoHDP risk, particularly in overweight/obese women, regardless of GDM status. Future preventive strategies should integrate multifaceted approaches addressing maternal BMI and glucose regulation to improve maternal and neonatal outcomes.

Association of early onset gestational diabetes mellitus with postpartum glucose intolerance

Background

This study aimed to investigate the association between postpartum glucose intolerance and the timing of gestational diabetes mellitus (GDM) diagnosis according to criteria from the International Association of Diabetes and Pregnancy Study Groups (IADPSG).

Methods

A single-center retrospective case-control study involving patients diagnosed with GDM according to IADPSG criteria was conducted. Patients underwent a postpartum 75 g oral glucose tolerance test (OGTT) and were divided into 2 groups: normal (control) and abnormal glucose tolerance (AGT). Gestational age at GDM diagnosis and the maternal and neonatal outcomes were compared between the groups.

Results

Data from 177 controls and 102 patients diagnosed with AGT were analyzed. The AGT group exhibited a higher pre-pregnancy body mass index, family history of diabetes, glycated hemoglobin level at the initial visit, and total daily insulin dose, but a lower rate of GDM diagnosis at 24-32 weeks' gestation. GDM diagnosed before 24 weeks' gestation was independently associated with AGT (adjusted odds ratio 2.18 [95% confidence interval 1.28-3.73]; p < 0.01]). Additionally, a higher proportion of patients diagnosed with GDM before 24 weeks' gestation had a lower disposition index (27.1% versus 14.8%; p = 0.01).

Conclusions

Patients diagnosed with GDM at < 24 weeks' gestation were at higher risk for postpartum glucose intolerance than those diagnosed at 24-32 weeks. The lower disposition index in patients early diagnosed highlights the need for tailored postpartum follow-up to address their specific risks.

Impact of maternal overweight/obesity and high fasting plasma glucose on adverse perinatal outcomes in early gestational diabetes mellitus

AIM

To elucidate risk factors associated with adverse perinatal outcomes in early-gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

A dataset of 385 early-GDM cases from a prospective cohort was analyzed. Early-GDM was diagnosed if one or more of the following criteria were met: fasting plasma glucose (PG) levels of 92-125 mg/dL, 1-h PG levels ≥180 mg/dL, and 2-h PG levels ≥153 mg/dL during a 75-g oral glucose tolerance test before 20 weeks of gestation. Multivariate analysis was used to examine associations between candidate risk factors and a composite outcome of maternal and neonatal adverse events.

RESULTS

Pre-pregnancy overweight/obesity (pre-pregnancy body mass index [BMI] ≥25.0 kg/m2) was significantly associated with a higher risk of the composite outcome compared with normal weight (pre-pregnancy BMI of 18.5-24.9 kg/m2), an adjusted risk ratio (aRR) of 1.44 (95% confidence interval [CI]: 1.08-1.93), and an adjusted risk difference (aRD) of 13.6% (95% CI: 2.6-24.6%). Compared with fasting PG levels below 92 mg/dL, levels between 95 and 125 mg/dL were associated with a significantly higher risk of the composite outcome, with an aRR and aRD of 1.42 (95% CI: 1.01-1.99) and 12.9% (95% CI: 0.3-25.5%), respectively.

CONCLUSIONS

Early-GDM, combined with pre-pregnancy overweight/obesity and/or fasting PG levels of 95-125 mg/dL, is associated with a higher risk of adverse perinatal outcomes and should be prioritized for intervention.

Risk of Gestational Diabetes in Women With PCOS Based on Body Mass Index: The Japan Environment and Children's Study

CONTEXT

Women with polycystic ovary syndrome (PCOS), which is the most common endocrine disorder in women of reproductive age, have a potentially increased risk of gestational diabetes mellitus (GDM).

OBJECTIVE

To examine the impact of PCOS on GDM based on maternal body mass index (BMI) using data from a large birth cohort study in Japan.

DESIGN

Prospective observational study using data from the Japan Environment and Children's Study (JECS).

PARTICIPANTS

Singleton pregnancies in the JECS during 2011-2014 were included. Mothers with HbA1c levels of ≥6.5% in the first trimester and history of diabetes mellitus or steroid use during pregnancy were excluded.

MAIN OUTCOME MEASURES

Participants were categorized according to their prepregnancy BMIs: G1 (<18.5 kg/m2), G2 (18.5-19.99 kg/m2), G3 (20.0-22.99 kg/m2), G4 (23.0-24.99 kg/m2), and G5 (≥25.0 kg/m2). The impact of PCOS on early(Ed) and late-onset(Ld) GDM for each group was estimated using a multiple logistic regression model.

RESULTS

We included 92 774 participants, comprising 2012 PCOS(+) cases. GDM occurrence was higher in women with PCOS (P < .001). PCOS had no effect on GDM in G1, G2, and G3. In G4, PCOS increased the risk of Ed GDM (adjusted odds ratio [aOR]: 3.27; 95% confidence interval [CI], 1.29-8.29). In G5, PCOS increased the risk of both Ed (aOR: 2.48; 95% CI, 1.53-4.02) and Ld GDM (aOR: 1.94; 95% CI, 1.23-3.07).

CONCLUSION

The impact of PCOS on GDM occurrence depended on the prepregnancy BMIs, which may facilitate personalized preconception counseling among women with PCOS.

Relationship between preconception protein intake and gestational diabetes mellitus: The Japan Environment and Children's Study

AIMS

To investigate the relationship between preconception protein intake and the risk of gestational diabetes mellitus (GDM).

METHODS

We analyzed data from the Japan Environment and Children's Study, focusing on 80,346 participants (mean age 31.3 ± 4.9 years; mean body mass index 21.2 ± 3.2 kg/m2) who delivered between 2011 and 2014. These participants had no history of diabetes mellitus, no previous diagnosis of GDM, and did not use steroids during pregnancy. Participants were categorized into five groups based on preconception protein energy ratio quintiles (Q1 and Q5 represent the lowest and highest intake, respectively). Continuous variables were compared using one-way analysis of variance or the Kruskal-Wallis test, and categorical variables using chi-square tests. Primary outcomes were GDM, early-diagnosed GDM (Ed-GDM, diagnosed at <24 weeks), and late-diagnosed GDM (Ld-GDM, diagnosed at >24 weeks). Adjusted odds ratios (aORs) and 95 % confidence intervals (CIs) were calculated using logistic regression analysis with the middle quintile (Q3) as the reference.

RESULTS

Multiple logistic regression analysis revealed that using the Q3 group as the reference, the Q5 group had a higher risk of Ed-GDM (aOR 1.48, 95 % CI 1.06-2.07), whereas the Q1 group had a lower risk of Ed-GDM (aOR 0.69, 95 % CI 0.48-0.996). However, no significant differences were observed in the risk of GDM and Ld-GDM.

CONCLUSIONS

Higher preconception protein intake was associated with increased Ed-GDM risk. Further research is needed to refine dietary recommendations for preconception protein intake.

Gestational diabetes mellitus and adverse maternal and perinatal outcomes in twin and singleton pregnancies: a systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the risk of adverse maternal and perinatal complications between twin and singleton pregnancies affected by gestational diabetes mellitus and the respective group without gestational diabetes mellitus (controls).

DATA SOURCES

A literature search was performed using MEDLINE, Embase, and Cochrane from January 1980 to May 2023.

STUDY ELIGIBILITY CRITERIA

Observational studies reporting maternal and perinatal outcomes in singleton and/or twin pregnancies with gestational diabetes mellitus vs controls were included.

METHODS

This was a systematic review and meta-analysis. Pooled estimate risk ratios with 95% confidence intervals were generated to determine the likelihood of adverse pregnancy outcomes between twin and singleton pregnancies with and without gestational diabetes mellitus. Heterogeneity among studies was evaluated in the model and expressed using the I2 statistic. A P value of <.05 was considered statistically significant. The meta-analyses were performed using Review Manager (RevMan Web). Version 5.4. The Cochrane Collaboration, 2020. Meta-regression was used to compare relative risks between singleton and twin pregnancies. The addition of multiple covariates into the models was used to address the lack of adjustments.

RESULTS

Overall, 85 studies in singleton pregnancies and 27 in twin pregnancies were included. In singleton pregnancies with gestational diabetes mellitus, compared with controls, there were increased risks of hypertensive disorders of pregnancy (relative risk, 1.85; 95% confidence interval, 1.69-2.01), induction of labor (relative risk, 1.36; 95% confidence interval, 1.05-1.77), cesarean delivery (relative risk, 1.31; 95% confidence interval, 1.24-1.38), large-for-gestational-age neonate (relative risk, 1.61; 95% confidence interval, 1.46-1.77), preterm birth (relative risk, 1.36; 95% confidence interval, 1.27-1.46), and admission to the neonatal intensive care unit (relative risk, 1.43; 95% confidence interval, 1.38-1.49). In twin pregnancies with gestational diabetes mellitus, compared with controls, there were increased risks of hypertensive disorders of pregnancy (relative risk, 1.69; 95% confidence interval, 1.51-1.90), cesarean delivery (relative risk, 1.10; 95% confidence interval, 1.06-1.13), large-for-gestational-age neonate (relative risk, 1.29; 95% confidence interval, 1.03-1.60), preterm birth (relative risk, 1.19; 95% confidence interval, 1.07-1.32), and admission to the neonatal intensive care unit (relative risk, 1.20; 95% confidence interval, 1.09-1.32) and reduced risks of small-for-gestational-age neonate (relative risk, 0.89; 95% confidence interval, 0.81-0.97) and neonatal death (relative risk, 0.50; 95% confidence interval, 0.39-0.65). When comparing relative risks in singleton vs twin pregnancies, there was sufficient evidence to suggest that twin pregnancies have a lower relative risk of cesarean delivery (P=.003), have sufficient adjustment for confounders, and have lower relative risks of admission to the neonatal intensive care unit (P=.005), stillbirths (P=.002), and neonatal death (P=.001) than singleton pregnancies.

CONCLUSION

In both singleton and twin pregnancies, gestational diabetes mellitus was associated with an increased risk of adverse maternal and perinatal outcomes. In twin pregnancies, gestational diabetes mellitus may have a milder effect on some adverse perinatal outcomes and may be associated with a lower risk of neonatal death.

Cord blood triglyceride and total cholesterol in preterm and term neonates: reference values and associated factors from the Japan Environment and Children's Study

This study aimed to investigate the associations between cord serum total cholesterol (TC) and triglyceride (TG)levels and perinatal factors and determine the reference levels of cord blood TC and TG in Japanese neonates. This was a prospective birth cohort study using data from the Japan Environment and Children's Study, which included data on births from 2011 to 2014 in Japan. TC and TG levels were determined in cord blood samples. A total of 70,535 pairs of neonates (male: 36,001, female: 34,524) and mothers were included. The mean cord blood TC and TG levels were 72.2 mg/dL and 24.4 mg/dL, respectively. Multiple regression analyses revealed that gestational age and birth weight were significantly associated with cord blood TC (coefficient -2.35, 95% confidence interval [CI] -2.40 - -2.22 and coefficient 0.002, 95% CI 0.002-0.003, respectively) and TG (coefficient 3.09, 95% CI 3.01-3.17 and coefficient - 0.009, 95% CI - 0.009-0.008, respectively) levels. Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories.    Conclusion: Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories in Japanese newborns. Maternal complications such as maternal parity, HDP, PROM, maternal obesity and income level were associated with cord TC and TG levels. What is Known: • No studies have ascertained the reference levels of cord blood lipid levels in Japan. What is New: • Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term.

Interventions to increase the uptake of postpartum diabetes screening among women with previous gestational diabetes: a systematic review and Bayesian network meta-analysis

OBJECTIVE

This study aimed to summarize the current interventions aimed at improving postpartum diabetes screening attendance and to compare their effectiveness.

DATA SOURCES

Literature searches were conducted in the Web of Science, Embase, Cochrane Library, CINAHL, and PubMed from inception to March 20, 2023.

STUDY ELIGIBILITY CRITERIA

Quantitative studies involving an intervention to increase postpartum diabetes screening attendance among women with gestational diabetes mellitus were included.

METHODS

The Joanna Briggs Institute checklists were used for the quality appraisal of the included studies. A Bayesian network meta-analysis was performed to synthesize the comparative effectiveness of the relevant interventions aimed at improving postpartum diabetes screening rates.

RESULTS

A total of 40 studies were included in this review with pooled data from 17,123 women. Studies included randomized controlled trials (n=11, including 3 US-based studies and 8 non-US-based studies) and nonrandomised studies (n=29, including 13 US-based studies and 16 non-US-based studies). Of the 14 studies that reported screening outcomes, 11 detected early type 2 diabetes at a rate ranging from 2.0% to 23.0%. The types of interventions identified included reminders (eg, postal letters, emails, and phone messages), educational interventions, screening methods and delivery, policy changes, antenatal groups, and multimodal interventions. Based on the network meta-analysis from randomized controlled trials, antenatal group intervention, which refers to antenatal patient education delivered in groups (1 US-based study), had the highest probability to be the most effective intervention (odds ratio, 10; 95% confidence interval, 1.6-77.0), followed by one-to-one educational intervention with written educational materials or counselling (odds ratio, 6.9; 95% confidence interval, 3.6-16.0). The results from nonrandomized studies indicated that flexible screening methods and delivery (2 US-based studies) had the greatest impact on screening uptake (odds ratio, 3.9; 95% confidence interval, 1.8-10.0), followed by educational interventions (1 US-based study and 2 non-US-based studies) with antenatal patient education and written educational materials (odds ratio, 3.4; 95% confidence interval, 1.9-6.3) and antenatal groups (odds ratio, 3.3; 95% confidence interval, 1.7-6.7).

CONCLUSION

The presented evidence suggests that antenatal patient education delivered in groups and offering more flexible screening methods were associated with the greatest increase in attendance. The multimodal interventions and reminders could still be important if they were more theoretically grounded and were more integrated into the healthcare system.

Complications and risk factors of early-onset versus late-onset gestational diabetes mellitus: A cohort study from Saudi Arabia

OBJECTIVES

To contribute to this discussion by comparing the complications associated with early-diagnosed versus (vs.) late-diagnosed gestational diabetes mellitus (GDM) for mothers and infants in order to provide baseline data that might guide future changes in the current recommendations for screening.

METHODS

The study compares the risk factors and complications for early- vs. late-diagnosed GDM in a cohort from Saudi Arabia. Prenatal, perinatal, postpartum, and neonatal variables were compared between the early vs. late-diagnosed GDM groups using information gathered from the patient's hospital records.

RESULTS

Significant predictors of early-diagnosed GDM included pregestational BMI and GDM history. Additionally, early diagnosis of GDM was linked to a higher incidence of pre-eclampsia and intrauterine fetal death. Women with early-diagnosed GDM also required more glycemic control interventions, like administering insulin and metformin and controlling their diet. The fetal birth weight and postpartum BMI were significantly higher in the early onset GDM group. The need for insulin and pre-eclampsia were significant factors linked to an early diagnosis of GDM, according to a logistic regression analysis.

CONCLUSION

Therefore, the current findings emphasize the need for early screening in pregnant women with high pregestational BMI and a history of GDM and show that those with early-onset GDM more likely to need insulin therapy and be at a higher risk of developing pre-eclampsia.

Evaluating glucose variability through OGTT in early pregnancy and its association with hypertensive disorders of pregnancy in non-diabetic pregnancies: a large-scale multi-center retrospective study

BACKGROUND

Recent evidence suggests increased glucose variability (GV) causes endothelial dysfunction, a central pathology of hypertensive disorders of pregnancy (HDP). We aimed to investigate the association between GV in early pregnancy and subsequent HDP development among non-diabetes mellitus (DM) pregnancies.

METHODS

This multicenter retrospective study used data from singleton pregnancies between 2009 and 2019. Among individuals who had 75 g-OGTT before 20 weeks of gestation, we evaluated GV by 75 g-OGTT parameters and examined its relationship with HDP development, defining an initial-increase from fasting-plasma glucose (PG) to 1-h-PG and subsequent-decrease from 1-h-PG to 2-h-PG.

RESULTS

Approximately 3.0% pregnancies (802/26,995) had 75 g-OGTT before 20 weeks of gestation, and they had a higher prevalence of HDP (14.3% vs. 7.5%). The initial-increase was significantly associated with overall HDP (aOR 1.20, 95% CI 1.02-1.42), and the subsequent-decrease was associated with decreased and increased development of early-onset (EoHDP: aOR 0.56, 95% CI 0.38-0.82) and late-onset HDP (LoHDP: aOR 1.38, 95% CI 1.11-1.73), respectively.

CONCLUSIONS

A pattern of marked initial-increase and minor subsequent-decrease (i.e., sustained hyperglycemia) was associated with EoHDP. Contrarily, the pattern of marked initial-increase and subsequent-decrease (i.e., increased GV) was associated with LoHDP. This provides a new perspective for future study strategies.

Does fasting plasma glucose values 5.1-5.6 mmol/l in the first trimester of gestation a matter?

Objectives

The aim of the study was to investigate the effect of treatment on pregnancy outcomes among women who had fasting plasma glucose (FPG) 5.1-5.6 mmol/l in the first trimester of pregnancy.

Methods

We performed a secondary-analysis of a randomized community non-inferiority trial of gestational diabetes mellitus (GDM) screening. All pregnant women with FPG values range 5.1-5.6 mmol/l in the first trimester of gestation were included in the present study (n=3297) and classified to either the (i) intervention group who received treatment for GDM along with usual prenatal care (n=1,198), (ii) control group who received usual-prenatal-care (n=2,099). Macrosomia/large for gestational age (LGA) and primary cesarean-section (C-S) were considered as primary-outcomes. A modified-Poisson-regression for binary outcome data with a log link function and robust error variance was used to RR (95%CI) for the associations between GDM status and incidence of pregnancy outcomes.

Results

The mean maternal age and BMI of pregnant women in both study groups were similar. There were no statistically significant differences in the adjusted risks of adverse pregnancy outcomes, including macrosomia, primary C-S, preterm birth, hyperbilirubinemia, preeclampsia, NICU-admission, birth trauma, and LBW both groups.

Conclusions

It is found that treating women with first-trimester FPG values of 5.1-5.6 mmol/l could not improve adverse pregnancy outcomes including macrosomia, Primary C-S, Preterm birth, hypoglycemia, hypocalcemia, preeclampsia, NICU admission, Birth trauma and LBW. Therefore, extrapolating the FPG cut-off point of the second trimester to the first -which has been proposed by the IADPSG, might therefore not be appropriate.

Clinical Trial Registration

https://www.irct.ir/trial/518, identifier IRCT138707081281N1.

Maternal triglyceride levels and neonatal outcomes: The Japan Environment and Children's Study

BACKGROUND

Although maternal triglyceride (TG) is important for fetal growth, there are few large cohort studies investigating the relationships between maternal TG during pregnancy and neonatal outcomes.

OBJECTIVES

The objective of this study was to investigate the associations between maternal TG during the second and third trimesters and neonatal outcomes including preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA).

METHODS

This was a prospective birth cohort study using data of the Japan Environment and Children's Study included data of births from 2011-2014 in Japan including 79,519 pairs. Participants were divided into tertiles according to maternal TG in the second or third trimesters. Multiple logistic regression modeling was used to examine the risks of LBW, SGA, LGA and PTB in association with maternal TG levels in the second or third trimesters RESULTS: In the second trimester, compared with reference TG group (T2), women in higher TG group (T3) and lower TG group (T1) were also at increased risk of LGA (aOR 1.20, 95% CI 1.11-1.29) and SGA (aOR 1.25, 95% CI 1.10-1.41), respectively. In the third trimester, women in T3 and T1 were at increased risk of LGA (aOR 1.27, 95% CI 1.17-1.38) and SGA (aOR 1.17, 95% CI 1.02-1.34), respectively.

CONCLUSION

In this study, higher maternal TG levels in the second or third trimesters were associated with risks of LGA, however, lower maternal TG levels in the second or third trimesters were conversely associated with risks of SGA.

Predictive and Prognostic Value of Plasma Zonulin for Gestational Diabetes Mellitus in Women at 24-28 Weeks of Gestation

OBJECTIVE

We aimed to examine the predictive and prognostic value of plasma zonulin for gestational diabetes mellitus (GDM) in women at 24-28 weeks of gestation.

METHODS

This retrospective study was carried out with pregnant women with GDM (n=98) and normal glucose tolerance (control group) (n=132). GDM was diagnosed according to American Diabetes Association (ADA) criteria with a one-step 75-g OGTT at 24-28 gestational weeks. Their serum zonulin levels measured during one-step 75-g OGTT and perinatal outcomes were compared, and the cut-off value of plasma zonulin for the prediction of GDM was calculated with receiver operating characteristic curve analysis.

RESULTS

Plasma zonulin level was significantly higher in women with GDM compared to controls (28.8±24.9 and 7.3±11.3 ng/mL, respectively). According to logistic regression analysis, plasma zonulin levels and GDM were statistically significant. The plasma zonulin cut-off value was>45.2 ng/mL. The rate of cesarean section, the rate of meconium in the amniotic fluid, and the need for admission to the neonatal intensive care unit significantly differed between women with GDM and controls.

CONCLUSION

In pregnant women with GDM, plasma zonulin increases, and with the cut-off level of>45.2 ng/mL, it can predict GDM with values of sensitivity and specificity levels significantly higher in pregnant women with GDM, suggesting that it can be used as a tool for its screening and early diagnosis.

Association of Chlamydia trachomatis infection with pregnancy outcomes among Japanese pregnant women: The Japan environment and children's study

This study aimed to investigate the impact of Chlamydia trachomatis (CT) infection on pregnancy outcome in pregnant Japanese women. We utilized the data from a nationwide birth cohort study, the Japan Environment and Children's Study (JECS), for this study. We enrolled 26,385 individuals who could refer to data on pregnancy outcomes and confounding factors, with data on CT. Binominal logistic regression models were used to determine whether pregnant women with CT positivity were at more risk of experiencing adverse pregnancy outcomes, preterm birth (PTB), preterm prelabor rupture of membrane (pPROM), low birth weight (LBW) infants, small for gestational age (SGA) births, or hypertensive disorders of pregnancy (HDP). After adjusting for maternal age, parity, marital status, smoking status, and education status, there were no significantly increased risks of PTB, pPROM, LBW infants, SGA, and HDP in the odds ratios. No significant increase in the risk of adverse pregnancy outcomes was observed in any of the subgroup analyses, which were limited to the pregnancy women in Fukushima prefecture, where CT screening could be confirmed at 28-30 weeks of gestation. We believe that the results of this study will make a significant contribution to the future of medical care for pregnant women in Japan. Our findings are important for medical practitioners to contribute to the future medical treatment of Japanese pregnant women, and also to contribute to pre-conception care for Japanese society as a whole, including pregnant women.

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

We aimed to examine the impact of a preconception pro-inflammatory diet on gestational diabetes mellitus (GDM) using singleton pregnancy data from the Japan Environment and Children’s Study involving live births from 2011 to 2014. Individual meal patterns before pregnancy were used to calculate the dietary inflammatory index (DII). Participants were categorized according to DII quartiles 1−4 (Q1 and Q4 had the most pro-inflammatory and anti-inflammatory diets, respectively). The participants were stratified into five groups by pre-pregnancy body mass index (BMI): G1 to G5 (<18.5 kg/m2, 18.5 to <20.0 kg/m2, 20.0 to <23.0 kg/m2, 23.0 to <25.0 kg/m2, and ≥25.0 kg/m2, respectively). A multiple logistic regression model was used to estimate the effect of the anti-inflammatory diet on GDM, early diagnosed (Ed)-GDM, and late diagnosed (Ld)-GDM in each BMI group. Trend analysis showed that the risk of GDM, Ed-GDM, and Ld-GDM increased with increased pre-pregnancy BMI values. In the G4 group, the risk of Ed-GDM increased in Q2 and Q4. This study suggests that, although higher maternal BMI increases the risk of GDM, the effect of a preconception pro-inflammatory diet on the occurrence of GDM depends on pre-pregnancy BMI. This result may facilitate personalized preconception counseling based on maternal BMI.

Gestational weight gain as a risk factor for dystocia during first delivery: a multicenter retrospective cohort study in Japan

Background

Dystocia is a common obstetric complication among nulliparous women, which requires medical intervention and carries the risk of negative maternal and neonatal outcomes. Our aim was to examine the association between body mass index (BMI) and the occurrence of dystocia. We also identified cutoffs of gestational weight gain, based on pre-pregnancy BMI, associated with the risk of dystocia.

Methods

This was a multicenter, retrospective, cohort study conducted in two tertiary Maternal–Fetal medicine units in Fukushima, Japan. The study population included nullipara women who delivered at either of the two units between January 1, 2013, and December 31, 2020. Women (n = 2597) were categorized into six groups (G) based on their pre-pregnancy BMI: G1 (< 18.5 kg/m²), G2 (18.5 to < 20.0 kg/m²), G3 (20.0 to < 23.0 kg/m²), G4 (23.0 to < 25.0 kg/m²), G5 (25.0 to < 30.0 kg/m²), and G6 (≥ 30.0 kg/m²). Using G3 as a reference, multiple logistic regression analyses were performed to estimate the risk of dystocia for each BMI category. Receiver operating characteristic curve analyses were performed to determine the cutoff value of gestational weight gain for the risk of dystocia.

Results

The highest BMI category (G6) was an independent risk factor for dystocia (adjusted odds ratio, 3.0; 95% confidence interval, 1.5–5.8). The receiver operating characteristic curve analysis revealed no association between gestational weight gain and the occurrence of dystocia in G5 and G6 (P = 0.446 and P = 0.291, respectively). For G1 to G4, AUC and predictive cutoffs of gestational weight gain for dystocia were as follows: G1, AUC 0.64 and cutoff 11.5 kg (P < 0.05); G2, AUC 0.63 and cutoff 12.3 kg (P < 0.05); G3, AUC 0.67 and cutoff 14.3 kg (P < 0.01); and G4, AUC 0.63 and cutoff 11.5 kg (P < 0.05).

Conclusion

A pre-pregnancy BMI > 30.0 kg/m² was an independent risk factor for dystocia. For women with a pre-pregnancy BMI < 25.0 kg/m², the risk of dystocia increases as a function of gestational weight gain. These findings could inform personalized preconception care for women to optimize maternal and neonatal health.

Updates for hyperglycemia in pregnancy: the ongoing journey for maternal-neonatal health

We summarize updates of hyperglycemia in pregnancy as well as debate of diagnosis of criteria of gestational diabetes. We also point out several unsovled issues of gestataional diabetes that remain further investigations.

Preconception vitamin D intake and obstetric outcomes in women using assisted reproductive technology: the Japan Environment and Children’s Study

Background

In reproductive medicine, vitamin D (VitD) is of particular interest because its deficiency has been linked to various infertility issues. Thus, preconception care, including appropriate VitD supplementation, is essential, especially in women using assisted reproductive technology (ART). Despite the therapeutic benefits of VitD, adverse events due to a high daily intake may influence obstetric outcomes. However, the effects of either low or high preconception VitD intake on obstetric outcomes, including the outcomes in women who used ART, remain unclear. Therefore, the aim of this study was to examine the association between pre-pregnancy daily VitD intake and obstetric outcomes in Japanese women, including those who conceived through ART.

Methods

Data were obtained from the Japan Environment and Children’s study database comprising 92,571 women recruited between January 2011 and March 2014 in Japan. Participants were categorized into five quintiles according to pre-pregnancy VitD intake (Q1 and Q5 had the lowest and highest VitD intake, respectively) and stratified according to the use of ART. Multiple logistic regression was performed to identify the effects of pre-pregnancy VitD intake on preterm birth (PTB), low-birth weight infant (LBW), and small for gestational age (SGA).

Results

Using Q3 (middle VitD intake) as a reference, our analysis revealed that Q5 (highest VitD intake) showed an increased risk of LBW < 1500 g (adjusted odds ratio [aOR]: 1.09, 95% confidence interval [CI]: 1.00–1.18) and SGA (aOR: 1.26, 95% CI: 1.14–1.39) among women who conceived without ART. Among women who conceived with ART, we found that Q5 (highest VitD intake) showed an increased risk of PTB at < 37 weeks (aOR: 2.05, 95% CI: 1.27–3.31).

Conclusion

The present study revealed that higher VitD intake before pregnancy may affect perinatal outcomes, particularly in women using ART. Our findings may facilitate personalized preconceptional counseling regarding VitD intake based on the method of conception, especially among women using ART.

Risk of Adverse Pregnancy Outcomes in Young Women with Thyroid Cancer: A Systematic Review and Meta-Analysis

Simple Summary

This meta-analysis of 22 articles investigated whether thyroidectomy or radioactive iodine treatment (RAIT) in patients with differentiated thyroid cancer was associated with an increase in adverse pregnancy outcomes, such as miscarriage, preterm delivery, and congenital malformations. The results of this meta-analysis suggest that thyroid cancer treatment, including RAIT, is not associated with an increased risk of adverse pregnancy outcomes, including miscarriage, preterm labor, and congenital anomalies.

Abstract

This meta-analysis investigated whether thyroidectomy or radioactive iodine treatment (RAIT) in patients with differentiated thyroid cancer (DTC) was associated with an increase in adverse pregnancy outcomes, such as miscarriage, preterm delivery, and congenital malformations. A total of 22 articles (5 case-control and 17 case series studies) from 1262 studies identified through a literature search in the PubMed and EMBASE databases from inception up to 13 September 2021 were included. In patients with DTC who underwent thyroidectomy, the event rates for miscarriage, preterm labor, and congenital anomalies were 0.07 (95% confidence interval [CI], 0.05–0.11; 17 studies), 0.07 (95% CI, 0.05–0.09; 14 studies), and 0.03 (95% CI, 0.02–0.06; 17 studies), respectively. These results are similar to those previously reported in the general population. The risk of miscarriage or abortion was increased in patients with DTC when compared with controls without DTC (odds ratio [OR], 1.80; 95% CI, 1.28–2.53; I² = 33%; 3 studies), while the OR values for preterm labor and the presence of congenital anomalies were 1.22 (95% CI, 0.90–1.66; I² = 62%; five studies) and 0.73 (95% CI, 0.39–1.38; I² = 0%; two studies) respectively, which showed no statistical significance. A subgroup analysis of patients with DTC according to RAIT revealed that the risk of miscarriage, preterm labor, or congenital anomalies was not increased in the RAIT group when compared with patients without RAIT. The results of this meta-analysis suggest that thyroid cancer treatment, including RAIT, is not associated with an increased risk of adverse pregnancy outcomes, including miscarriage, preterm labor, and congenital anomalies.

Association of placenta previa with placental size in Japanese women: A study from a single tertiary referral center

AIM

The effect of placenta previa on age-specific placental size has not yet been elucidated. This study aimed to examine the effect of placenta previa on the Japanese standardized z-scores of placental size.

METHODS

This retrospective cohort study included Japanese participants from Ohta Nishinouchi Hospital with single pregnancies who gave birth during 2013-2019. The participants were categorized into two groups based on the presence or absence of placenta previa. Multiple linear regression analyses were used to identify the association of placenta previa with the z-score of placental size, after adjusting for factors, such as maternal smoking status, maternal age, assisted reproductive technology, myoma uteri, uterine anomaly, maternal hypertension at the time of pregnancy, and body mass index before pregnancy.

RESULTS

A total of 4071 Japanese women (76 with placenta previa and 3995 without placenta previa) were identified. Placenta previa significantly increased the placental weight z-score (partial regression coefficient: 0.44, 95% confidence interval 0.10-0.70, p < 0.001).

CONCLUSION

Placenta previa increased the age-specific placental size. Further studies are required to examine whether placenta previa is associated with the risk of obstetrics complications related to the placental size.

Age at menarche and risk of adverse obstetric outcomes during the first childbirth in Japan: The Japan Environment and Children's Study

AIM

Age at menarche is used as a risk indicator of gestational diabetes mellitus, preterm birth, and fetal growth. However, little is known regarding the age impact on obstetric outcomes among nulliparous women. This study investigated whether menarche age was correlated with obstetric outcomes among nulliparous women.

METHODS

We analyzed the data obtained for 37 645 singleton pregnancies between 2011 and 2014 in the Japan Environment and Children's Study. Age at menarche was categorized into the ≤9-, 10-, 11-, 12-, 13-, 14-, and ≥15-year-old groups (n = 363, 3155, 8390, 11 164, 6713, 5446, and 2414, respectively). We calculated the relative risk for cases of preterm birth <37 weeks, low birthweight <2500 g, small for gestational age, early and late-onset hypertension disorders of pregnancy, and early- and late-diagnosed (diagnosed < or ≧ 24 weeks) gestational diabetes mellitus using a reference of 12 years at menarche.

RESULTS

Women with an age at menarche ≤9 years showed an increased incidence of developing early-diagnosed gestational diabetes mellitus (relative risk: 2.42; 95% confidence interval: 1.05-5.60). A high body mass index before pregnancy increased the risk of developing gestational diabetes mellitus.

CONCLUSIONS

Age at menarche helped in assessing the risk of early-diagnosed gestational diabetes mellitus among nulliparous women. Future studies are needed to clarify the underlying mechanisms. This study is the first to use data from the largest prospective birth cohort study of Japan and to investigate the relationship between menarche age and obstetric outcomes among nulliparous women.

Association of glycated hemoglobin at an early stage of pregnancy with the risk of gestational diabetes mellitus among non-diabetic women in Japan: The Japan Environment and Children's Study

AIMS/INTRODUCTION

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy and is associated with adverse pregnancy outcomes. This study aimed to explore the associations between glycated hemoglobin (HbA1c) levels at the early stage of pregnancy and the GDM risk among non-diabetic women in a nationwide study in Japan. In addition, the relationship between GDM and adverse pregnancy outcomes was also analyzed.

MATERIALS AND METHODS

This cohort study (n = 89,799) used data from the Japan Environment and Children's Study. We stratified the participants into four groups according to HbA1c levels at an early stage of pregnancy. We investigated the association of HbA1c at an early stage of pregnancy with the risk of GDM, and of GDM with the risk of some representative adverse pregnancy outcomes, using the multiple logistic regression model with adjustment for potential confounders.

RESULTS

The adjusted odds ratio for GDM per 0.1 percentage point increase in HbA1c (%) was 1.20. The adjusted odds ratio for developing GDM was significantly increased in women from the HbA1c 5.0-5.4% category. GDM significantly increased the adjusted odds ratio for adverse pregnancy outcomes, such as hypertensive disorders of pregnancy, polyhydramnios and premature birth.

CONCLUSIONS

High-normal HbA1c levels at the early stage of pregnancy are significantly associated with GDM risk in women in Japan. GDM was significantly associated with adverse pregnancy outcomes.