Various screening and diagnosis approaches for gestational diabetes mellitus and adverse pregnancy outcomes: a secondary analysis of a randomized non-inferiority field trial

INTRODUCTION

We evaluate which screening and diagnostic approach resulted in the greatest reduction in adverse pregnancy outcomes due to increased treatment.

RESEARCH DESIGN AND METHODS

This study presents a secondary analysis of a randomized community non-inferiority trial conducted among pregnant women participating in the GULF Study in Iran. A total of 35 430 pregnant women were randomly assigned to one of the five prespecified gestational diabetes mellitus (GDM) screening protocols. The screening methods included fasting plasma glucose (FPG) in the first trimester and either a one-step or a two-step screening method in the second trimester of pregnancy. According to the results, participants were classified into 6 groups (1) First-trimester FPG: 100-126 mg/dL, GDM diagnosed at first trimester; (2) First trimester FPG: 92-99.9 mg/dL, GDM diagnosed at first trimester; (3) First trimester FPG: 92-99.9 mg/dL, GDM diagnosed at second trimester; (4) First trimester FPG: 92-99.9 mg/dL, healthy at second trimester; (5) First trimester FPG<92 mg/dL, GDM diagnosed at second trimester; (6) First trimester FPG<92 mg/dL, healthy at second trimester. For our analysis, we initially used group 6, as the reference and repeated the analysis using group 2, as the reference group. The main outcome of the study was major adverse maternal and neonatal outcomes.

RESULTS

Macrosomia and primary caesarean section occurred in 9.8% and 21.0% in group 1, 7.8% and 19.8% in group 2, 5.4% and 18.6% in group 3, 6.6% and 21.5% in group 4, 8.3% and 24.0% in group 5, and 5.4% and 20.0% in group 6, respectively. Compared with group 6 as the reference, there was a significant increase in the adjusted risk of neonatal intensive care unit (NICU) admission in groups 1, 3, and 5 and an increased risk of macrosomia in groups 1, 2, and 5. Compared with group 2 as the reference, there was a significant decrease in the adjusted risk of macrosomia in group 3, a decreased risk of NICU admission in group 6, and an increased risk of hyperglycemia in group 3.

CONCLUSIONS

We conclude that screening approaches for GDM reduced the risk of adverse pregnancy outcomes to the same or near the same risk level of healthy pregnant women, except for the risk of NICU admission that increased significantly in groups diagnosed with GDM compared with healthy pregnant women. Individuals with slight increase in FPG (92-100 mg/dL) at first trimester, who were diagnosed as GDM, had an even increased risk of macrosomia in comparison to those group of women with FPG 92-100 mg/dL in the first trimester, who were not diagnosed with GDM, and developed GDM in second trimester TRIAL REGISTRATION: IRCT138707081281N1 (registered: February 15, 2017).

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.

Umbilical cord blood concentration of connecting peptide (C-peptide) and pregnancy outcomes

Background

C-peptide offers potential as a marker to indicate childhood metabolic outcomes. Measuring C-peptide concentration might have better future utility in the risk stratification of neonates born to overweight or diabetic mothers. Prior research has tried to bring this matter into the light; however, the clinical significance of these associations is still far from reach. Here we sought to investigate the associations between fetomaternal metabolic variables and umbilical cord blood C-peptide concentration.

Methods

For the present study, 858 pregnant women were randomly selected from among a sub-group of 35,430 Iranian pregnant women who participated in a randomized community non-inferiority trial of gestational diabetes mellitus (GDM) screening. Their umbilical cord (UC) blood C-peptide concentrations were measured, and the pregnancy variables of macrosomia/large for gestational age (LGA) and primary cesarean section (CS) delivery were assessed. The variation of C-peptide concentrations among GDM and macrosomia status was plotted. Due to the skewed distribution of C-peptide concentration in the sample, median regression analysis was used to identify potential factors related to UC C-peptide concentration.

Results

In the univariate model, positive GDM status was associated with a 0.3 (95% CI: 0.06 − 0.54, p = 0.01) increase in the median coefficient of UC blood C-peptide concentration. Moreover, one unit (kg) increase in the birth weight was associated with a 0.25 (95% CI: 0.03 − 0.47, p = 0.03) increase in the median coefficient of UC blood C-peptide concentration. In the multivariate model, after adjusting for maternal age, maternal BMI, and macrosomia status, the positive status of GDM and macrosomia were significantly associated with an increase in the median coefficient of UC blood C-peptide concentration (Coef.= 0.27, 95% CI: 0.13 − 0.42, p < 0.001; and Coef.= 0.34, 95% CI: 0.06 − 0.63, p = 0.02, respectively).

Conclusion

UC blood concentration of C-peptide is significantly associated with the incidence of maternal GDM and neonatal macrosomia. Using stratification for maternal BMI and gestational weight gain (GWG) and investigating molecular markers like Leptin and IGF-1 in the future might lay the ground to better understand the link between metabolic disturbances of pregnancy and UC blood C-peptide concentration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05081-4.

A Cluster Randomized Noninferiority Field Trial of Gestational Diabetes Mellitus Screening

CONTEXT

Although it is well-acknowledged that gestational diabetes mellitus (GDM) is associated with the increased risks of adverse pregnancy outcomes, the optimal strategy for screening and diagnosis of GDM is still a matter of debate.

OBJECTIVE

This study was conducted to demonstrate the noninferiority of less strict GDM screening criteria compared with the strict International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria with respect to maternal and neonatal outcomes.

METHODS

A cluster randomized noninferiority field trial was conducted on 35 528 pregnant women; they were scheduled to have 2 phases of GDM screening based on 5 different prespecified protocols including fasting plasma glucose in the first trimester with threshold of 5.1 mmol/L (92 mg/dL) (protocols A, D) or 5.6 mmol/L (100 mg/dL) (protocols B, C, E) and either a 1-step (GDM is defined if one of the plasma glucose values is exceeded [protocol A and C] or 2 or more exceeded values are needed [protocol B]) or 2-step approach (protocols D, E) in the second trimester. Guidelines for treatment of GDM were consistent with all protocols. Primary outcomes of the study were the prevalence of macrosomia and primary cesarean section (CS). The null hypothesis that less strict protocols are inferior to protocol A (IADPSG) was tested with a noninferiority margin effect (odds ratio) of 1.7.

RESULTS

The percentages of pregnant women diagnosed with GDM and assigned to protocols A, B, C, D, and E were 21.9%, 10.5%, 12.1%, 19.4%, and 8.1%, respectively. Intention-to-treat analyses satisfying the noninferiority of the less strict protocols of B, C, D, and E compared with protocol A. However, noninferiority was not shown for primary CS comparing protocol E with A. The odds ratios (95% CI) for macrosomia and CS were: B (1.01 [0.95-1.08]; 0.85 [0.56-1.28], C (1.03 [0.73-1.47]; 1.16 [0.88-1.51]), D (0.89 [0.68-1.17]; 0.94 [0.61-1.44]), and E (1.05 [0.65-1.69]; 1.33 [0.82-2.00]) vs A. There were no statistically significant differences in the adjusted odds of adverse pregnancy outcomes in the 2-step compared with the 1-step screening approaches, considering multiplicity adjustment.

CONCLUSIONS

The IADPSG GDM definition significantly increased the prevalence of GDM diagnosis. However, the less strict approaches were not inferior to other criteria in terms of adverse maternal and neonatal outcomes.

One-step versus two-step screening for diagnosis of gestational diabetes mellitus in Iranian population: A randomized community trial

OBJECTIVES

There is considerable worldwide controversy regarding optimal screening and diagnostic approaches for GDM. This study aimed to compare the prevalence, maternal and neonatal outcomes of a One-step with a Two-step approach for the screening and diagnosis of GDM in a large community sample of pregnant women.

METHODS

We conducted a secondary analysis of a randomized community non-inferiority trial of GDM screening in Iran. For the current study, all pregnant women who met the inclusion criteria were randomized into two groups for GDM screening. The first group of women (n = 14611) was screened by a One-step screening approach [75-g 2-h oral glucose tolerance test (OGTT)] and the second group (n = 14160) by a Two-step method (the 50-g glucose challenge test followed by the 100-g OGTT). All study participants were followed up until delivery, and the adverse maternal and neonatal outcomes were recorded in detail.

RESULTS

GDM was diagnosed in 9.3% of the pregnant women who were assigned to the One-step and in 5.4% of those assigned to the Two-step approach with a statistically significant difference between them (p < 0.001). Intention-to-treat analyses showed no significant differences between the One-step and the Two-step group in the unadjusted risks of the adverse pregnancy outcomes of macrosomia, primary cesarean-section, preterm birth, hypoglycemia, hypocalcemia, hyperbilirubinemia, preeclampsia, neonatal intensive care unit admission, birth trauma, low birth weight, and intrauterine fetal death. Results remained unchanged after adjustment for potential confounder variables including gestational age at enrollment and delivery, maternal body mass index, gestational weight gain, type of delivery, treatment modality, and GDM diagnosis in the first trimester.

CONCLUSION

We found that although the rates of GDM more than doubled with the One-step strategy, the One-step approach was similar to the Two-step approach in terms of maternal and neonatal outcomes. These findings may warn that more caution should be exercised in adopting the One-step method worldwide. Future research is needed to assess the long-term harm and benefits of those approaches to GDM screening for both mothers and their offspring.

CLINICAL TRIAL REGISTRATION

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

Prevalence, Associated Factors and Consequences of Unwanted Pregnancy in Iran

Background:

Unwanted pregnancy is a type of unplanned pregnancy that can endanger health of mother and child. This study aimed to determine the prevalence of unwanted pregnancy and its associated factors and consequences in Iran.

Methods:

This cross-sectional study was conducted in regions with low, moderate and high risk of maternal death. Two provinces were randomly selected in each region and 24 public health centers in each province during 2007–2012. Thereafter, 15–20 mothers, received at least one session of pregnancy care, were selected from each healthcare center. Data were gathered from both health records and interview with the mothers.

Results:

Of 2714 participants, 86.4% and 13.6% had respectively wanted and unwanted pregnancies. The underlying factors of unwanted pregnancy were determined as low distance with previous and next pregnancy, economic problems and have enough children. Moreover, there were significant relationships between unwanted pregnancy and place of residence, mother’s age and education, father’s education, pre-pregnancy care and number of previous pregnancies and children. There were also significant association between unwanted pregnancy and pregnancy care, anemia, exposure to risk factors and disease, intake of folic acid and iron, domestic violence, bitter memories and men’s participation.

Conclusion:

Although the prevalence of unwanted pregnancy has had a significant decrease in Iran, these mothers still require a higher level of educational, counseling and supportive services due to their low access to pregnancy care services and high exposure to associated risk factors.

Normalized Weight of Iranian Newborns According to Gestational Age: A Nationwide Study

BACKGROUND

By organizing birth weights according to gestational age at birth, reference weight values for different sex-gestational ages are provided.

METHODS

Data of 1,090,779 mothers and their neonates were gathered from 30 provinces of Iran. Pregnancy complications, maternal risk factors, type of delivery, maternal outcome, neonatal sex and APGAR score were determined. Birth weights were quantified into 3rd, 50th and 97th centile. Regression analysis was used to estimate birth weight of neonates.

RESULTS

Birth weight showed an enhancing trend with age; boys weighed more, multiparous women had higher neonatal birth weight, mothers with cardiovascular disease and diabetes mellitus had heavier infants, and mothers aged below 20 years had lower estimated infant birth weight. Gestational age (beta = 147.3) and male sex (beta = 114.9) were the most important independent variables, respectively for predicting birth weight (R-square = 0.512 and P < 0.001). In other words, with each unit increase in gestational age, birth weight would increase by 147.3 grams. Male fetuses were also 114.9 grams heavier than females of the same gestational age. Value of R-square shows relatively acceptable goodness of this statistical model.

CONCLUSION

A national reference for fetal growth patterns and related factors was determined in this study.

Tehran Survey of Potential Risk Factors for Multiple Births

Background

The multiple pregnancy incidence is increasing worldwide. This increased incidence is concerning to the health care system. This study aims to determine the frequency of multiple pregnancy and identify factors that affect this frequency in Tehran, Iran.

MATERIALS AND METHODS

This cross-sectional study included 5170 mothers in labor between July 6-21, 2015 from 103 hospitals with Obstetrics and Gynecology Wards. The questionnaire used in this study consisted of five parts: demographic characteristics; information related to pregnancy; information related to the infant; information regarding the multiple pregnancy; and information associated with infertility. We recruited 103 trained midwives to collect data related to the questionnaire from eligible participants through an interview and medical records review. Frequencies and odds ratios (OR) for the association between multiple pregnancy and the selected characteristics (maternal age, economic status, history of multiple pregnancy in first-degree relatives, and reproductive history) were computed by multiple logistic regression. Stata software, version 13 (Stata Corp, College Station, TX, USA) was used for all statistical analyses.

RESULTS

Multiple pregnancy had a prevalence of 1.48% [95% confidence interval (CI): 1.19-1.85]. After controlling for confounding variables, we observed a significant association between frequency of multiple pregnancy and mother's age (OR=1.04, 95% CI: 1.001-1.09, P=0.044), assisted reproductive technique (ART, OR=6.11, 95% CI: 1.7- 21.97, P=0.006), and history of multiple pregnancy in the mother's family (OR=5.49, 95% CI: 3.55-9.93, P=0.001).

CONCLUSION

The frequency of multiple pregnancy approximated results reported in previous studies in Iran. Based on the results, we observed significantly greater frequency of multiple pregnancy in older women, those with a history of ART, and a history of multiple pregnancy in the mother's family compared to the other variables.

Comparison of Metabolic and Hormonal Profiles of Women With and Without Premenstrual Syndrome: A Community Based Cross-Sectional Study

BACKGROUND

Premenstrual syndrome (PMS) is reported by up to 85% of women of reproductive age. Although several studies have focused on the hormone and lipid profiles of females with PMS, the results are controversial.

OBJECTIVES

This study was designed to investigate the association of hormonal and metabolic factors with PMS among Iranian women of reproductive age.

MATERIALS AND METHODS

This study was a community based cross-sectional study. Anthropometric measurements, biochemical parameters, and metabolic disorders were compared between 354 women with PMS and 302 healthy controls selected from among 1126 women of reproductive age who participated in the Iranian PCOS prevalence study. P values < 0.05 were considered significant.

RESULTS

Prolactin (PRL) and triglycerides (TG) were significantly elevated in women with PMS, whereas their testosterone (TES), high density lipoprotein (HDL) and 17-hydroxyprogesterone (17-OHP) levels were significantly less than they were in women without the syndrome (P < 0.05). After adjusting for age and body mass index (BMI), linear regression analysis demonstrated that for every one unit increase in PMS score there was 12% rise in the probability of having metabolic syndrome (P = 0.033).

CONCLUSIONS

There was a significant association between PMS scores and the prevalence of metabolic syndrome. Further studies are needed to confirm and validate the relationships between lipid profile abnormalities and metabolic disorders with PMS.

Development of strategies to reduce cesarean delivery rates in iran 2012-2014: a mixed methods study

BACKGROUND

With the change in population policy from birth control toward encouraging birth and population growth in Iran, repeated cesarean deliveries as a main reason of cesarean section are associated with more potential adverse consequences. The aim of this research was to explore effective strategies to reduce cesarean delivery rates in Iran.

METHODS

A mixed methodological study was designed and implemented. First, using a qualitative approach, concepts and influencing factors of increased cesarean delivery were explored. Based on the findings of this phase of the study, a questionnaire including the proposed strategies to reduce cesarean delivery was developed. Then in a quantitative phase, the questionnaire was assessed by key informants from across the country and evaluated to obtain more effective strategies to reduce cesarean delivery. Ten participants in the qualitative study included policy makers from the Ministry of Health, obstetricians, midwives and anthropologists. In the next step, 141 participants from private and public hospitals, insurance experts, Academic Associations of Midwifery, and policy makers in Maternity Health Affairs of Ministry of Health were invited to assess and provide feedback on the strategies that work to reduce cesarean deliveries.

RESULTS

Qualitative data analysis showed four concept related to increased cesarean delivery rates including; "standardization", "education", "amending regulations", and "performance supervision". Effective strategies extracted from qualitative data were rated by participants then, using ACCEPT derived from A as attainability, C as costing, C as complication, E as effectiveness, P as popularity, and T as timing table 19 strategies were detected as priorities.

CONCLUSIONS

Although developing effective strategies to reduce cesarean delivery rates is complex process because of the multi-factorial nature of increased cesarean deliveries, in this study we have achieved strategies that in the context of Iran could work.

The effects of sleep quality and duration in late pregnancy on labor and fetal outcome

BACKGROUND

Sleep disturbance is common during pregnancy. The aim of this study was to assess the effects of sleep duration and its quality on labor and fetal outcome.

METHOD

In a cross sectional study, primigravida women with singleton pregnancy (gestational age > 37 weeks) were recruited. Women with hypertension, diabetes mellitus, or those who needed emergency cesarean section were excluded. Data regarding the type and length of delivery, the quality of sleep as well as the neonates' weight and Apgar scores were recorded.

RESULTS

Totally, 457 participants were recruited. There was a significant correlation between the sleep duration and length of delivery stages. In most participants with more than 8 hours sleep, the first stage of delivery lasted between 6 and 10 hours. They had normal vaginal delivery with induction, and their neonates' Apgar score was > 9 (p = 0.029, p = 0.018, and p = 0.001, respectively). Most mothers with refreshing sleep had normal vaginal delivery with induction, their neonates weighted ≥ 2500 g and with Apgar score > 9 (p = 0.010, p < 0.001, and p = 0.005 respectively).

CONCLUSION

Sleep duration and quality of sleep can affect the type of delivery, length of labor stages, as well as neonates' Apgar score and birth weight. Such predictors of labor and fetal outcome should be assessed during prenatal evaluations.

Case-controlled study of the relationship between delivery method and incidence of post-partum urinary incontinence

The protective role of caesarean section against urinary incontinence was investigated in this descriptive case-controlled study of 125 women with urinary incontinence who had been referred to obstetrics and gynaecology clinics in Tehran, Iran, compared with 125 control women without urinary incontinence. A gynaecologist visited all women to complete a questionnaire and episiotomy scar, stress incontinence, and severity of cystocele and rectocele were also determined. Data were analysed by Student's t-test for quantitative variables, the chi(2)-test for qualitative variables and logistic regression. Increased age and body mass index were found to be significant risk factors of urinary incontinence (bivariate and multivariate analyses). There were also significant relationships between urinary incontinence and gravidity, parity, delivery mode, episiotomy, type of caesarean section (elective or emergency), cystocele, rectocele and chronic constipation (bivariate analysis only). There was no relationship between urinary incontinence and fetal birth weight or maternal employment status. The results suggest that caesarean section can decrease the rate of urinary incontinence.