Insulin resistance: the possible link between gestational diabetes mellitus and hypertensive disorders of pregnancy

Effect of oral glucose tolerance test-based insulin resistance on embryo quality in women with/without polycystic ovary syndrome

Objective

To explore the effects of insulin resistance (IR) on embryo quality and pregnancy outcomes in women with or without polycystic ovary syndrome (PCOS) undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

Methods

A retrospective cohort study concerning patients with/without PCOS who received gonadotropin-releasing hormone (GnRH)-antagonist protocol for IVF/ICSI from January 2019 to July 2022 was conducted. All the patients included underwent oral glucose tolerance test plus the assessment of insulin release within 6 months before the controlled ovarian stimulation. The Matsuda Index was calculated to diagnose IR. Two populations (PCOS and non-PCOS) were included and each was divided into IR and non-IR groups and analyzed respectively. The primary outcome was the high-quality day 3 embryo rate.

Results

A total of 895 patients were included (751 with PCOS and 144 without PCOS). For patients with PCOS, the IR group had a lower high-quality day 3 embryo rate (36.8% vs. 39.7%, p=0.005) and available day 3 embryo rate (67.2% vs. 70.6%, p<0.001). For patients without PCOS, there was no significant difference between the IR and non-IR groups in high-quality day 3 embryo rate (p=0.414) and available day 3 embryo rate (p=0.560). There was no significant difference in blastocyst outcomes and pregnancy outcomes for both populations.

Conclusion

Based on the diagnosis by the Matsuda Index, IR may adversely affect the day 3 embryo quality in patients with PCOS but not pregnancy outcomes. In women without PCOS, IR alone seems to have less significant adverse effects on embryo quality than in patients with PCOS. Better-designed studies are still needed to compare the differences statistically between PCOS and non-PCOS populations.

Evaluation of insulin secretion and insulin sensitivity in pregnant women: Application value of simple indices

The prevalence of gestational diabetes mellitus (GDM) is increasing annually, which poses substantial harm to the health of both mothers and children. Therefore, selection of clinically applicable and easily detectable indicators in the assessment of maternal insulin secretory function and insulin sensitivity in pregnant women undoubtedly holds great importance in evaluating the risk of GDM, guiding the choice of GDM therapy modalities, and improving the ability to provide early warning of adverse pregnancy outcomes. Compared with the classic clamp technique, many simple indices are more suited for use among pregnant women due to the low frequency of blood sampling and simple administration involved. While indices derived from fasting blood glucose and fasting insulin levels are most readily available, they are unable to provide information on the ability of insulin to manage the glucose load during pregnancy. Although the indices derived from the insulin and glucose values at each time point of the oral glucose tolerance test can provide a more comprehensive picture of the insulin sensitivity and insulin secretory function of the body, their application is constrained by the complexity of the procedure and associated high costs. Concomitantly, the findings from different studies are influenced by a variety of confounding factors, such as the gestational age during testing, race, and detection method. Furthermore, insulin secretory function and insulin sensitivity in pregnant women differ from those in non-pregnant women in that they change significantly with prolonged pregnancy; hence, there is an urgent need to develop a pregnancy-specific reference range. This article reviews the progress in the application of simple indices to help clinicians better understand their potential application in detecting GDM.

Adverse pregnancy outcomes and risk of type 2 diabetes in postmenopausal women

BACKGROUND

Although gestational diabetes mellitus and delivering high-birthweight infants are known to predict a higher risk of future type 2 diabetes mellitus, the association of hypertensive disorders of pregnancy and other adverse pregnancy outcomes with type 2 diabetes mellitus is not well established.

OBJECTIVE

This study aimed to examine the associations between different types of adverse pregnancy outcomes and incident type 2 diabetes mellitus among postmenopausal women.

STUDY DESIGN

The Women's Health Initiative, a nationwide cohort of postmenopausal women, collected self-reported history of adverse pregnancy outcomes, including gestational diabetes mellitus, hypertensive disorders of pregnancy, preterm birth, and delivering low- birthweight (<2500 g) or high-birthweight (>4500 g) infants. Participants were followed up annually for self-reported incident type 2 diabetes mellitus treated with medication from baseline (1993-1998) to March 2021. This study used logistic regression to examine the associations of any and individual adverse pregnancy outcomes with diabetes mellitus. Stratified analyses were performed to assess effect modification by body mass index, race and ethnicity, education, parity, breastfeeding, and age at first birth.

RESULTS

This analysis included 49,717 women without a history of diabetes mellitus at enrollment who had a least 1 pregnancy and responded to the questionnaire about adverse pregnancy outcomes. After adjusting for body mass index, demographic, lifestyle, and reproductive factors, gestational diabetes mellitus (odds ratio, 2.26; 95% confidence interval, 1.94-2.63), high birthweight (odds ratio, 1.30; 95% confidence interval, 1.18-1.44), and hypertensive disorders of pregnancy (odds ratio, 1.18; 95% confidence interval, 1.08-1.30) were independently associated with higher odds of type 2 diabetes mellitus, whereas preterm birth and low birthweight were not associated with diabetes mellitus risk. A history of ≥2 adverse pregnancy outcomes was associated with higher odds of type 2 diabetes mellitus (odds ratio, 1.55; 95% confidence interval, 1.28-1.88). This study further observed higher odds of type 2 diabetes mellitus (odds ratio, 3.69; 95% confidence interval, 2.38-5.70) among women with a history of both gestational diabetes mellitus and hypertensive disorders of pregnancy than those without any adverse pregnancy outcomes.

CONCLUSION

Postmenopausal women with a history of gestational diabetes mellitus, those delivering high-birthweight infants, or those with hypertensive disorders of pregnancy are at risk of future type 2 diabetes mellitus. In addition, women with ≥2 conditions had an augmented risk and might be prioritized for screening and prevention efforts for type 2 diabetes mellitus.

The physiological basis with uterine myometrium contractions from electro-mechanical/hormonal myofibril function to the term and preterm labor

Background

Most labor-related problems can be attributed to the uterine myometrium muscle, as this irritable tissue must suppress its irritability potential during pregnancy. Unfortunately, fewer studies have investigated the causes of this lack of suppression in preterm labor.

Methods

We conducted a scoping narrative review using three online databases (PubMed, Scopus, and Science Direct).

Results

The review focused on ion channel functions in the myometrium, including sodium channels [Na K-ATPase, Na-activated K channels (Slo2), voltage-gated (SCN) Na+, Na+ leaky channels, nonselective (NALCN) channels], potassium channels [KATP (Kir6) channels, voltage-dependent K channels (Kv4, Kv7, and Kv11), twin-pore domain K channels (TASK, TREK), inward rectifier Kir7.1, Ca2+-activated K+ channels with large (KCNMA1, Slo1), small (KCNN1-3), intermediate (KCNN4) conductance], and calcium channels [L-Type and T-type Ca2+ channels, calcium-activated chloride channels (CaCC)], as well as hyperpolarization-activated cation channels. These channels' functions are associated with hormonal effects such as oxytocin, estrogen/progesterone, and local prostaglandins.

Conclusion

Electromechanical/hormonal activity and environmental autocrine factors can serve as the primary practical basis for premature uterine contractions in term/preterm labor. Our findings highlight the significance of.1.the amplitude rate of hyperpolarization and the frequency of contractions,2.changes in the estrogen/progesterone ratio,3.Prostaglandins E/F involvement in initiating potential spikes and the increase of intracytoplasmic Ca2+.This narrative study highlights the range of hyperpolarization and the frequency of myometrium contractions as crucial factors. The synchronized complex progress of estrogen to progesterone ratio and prostaglandins plays a significant role in initiating potential spikes and increasing intracytoplasmic Ca2+, which further influences the contraction process during labor. Insights into myometrium physiology gained from this study may pave the way for much-needed new treatments to reduce problems associated with normal and preterm labor.

Dietary Plant Protein Intake Can Reduce Maternal Insulin Resistance during Pregnancy

Evidence suggests that the source of dietary protein may have an impact on insulin resistance, but no studies have explored it in pregnant populations. In this study, we combined a population study and an animal experiment to explore this effect. The population study was conducted with data from NHANES. Multiple linear regression was used to observe the association of protein intake with outcomes, including fasting glucose (GLU), insulin (INS), and HOMA-IR. In the animal experiment, 36 pregnant SD rats in three groups were orally administered 100% animal protein, 50% animal protein and 50% plant protein, or 100% plant protein, respectively. The intervention continued throughout the whole pregnancy. On day 19.5, maternal plasma was collected after overnight fasting, and metabolomics was performed using UPLC-MS. We found plant protein intake was negatively correlated with INS and HOMA-IR in the whole population. During the third trimester, a similar correlation was also observed. The animal experiment also presented the same result. In metabolomic analysis, changes in various metabolites and related pathways including FoxO and mTOR signaling pathways were observed. In conclusion, we found a negative association between dietary plant protein intake and maternal insulin resistance during pregnancy. Changes in some active substances and related metabolic pathways may play an important role.

TyGIS: improved triglyceride-glucose index for the assessment of insulin sensitivity during pregnancy

Background

The triglyceride-glucose index (TyG) has been proposed as a surrogate marker of insulin resistance, which is a typical trait of pregnancy. However, very few studies analyzed TyG performance as marker of insulin resistance in pregnancy, and they were limited to insulin resistance assessment at fasting rather than in dynamic conditions, i.e., during an oral glucose tolerance test (OGTT), which allows more reliable assessment of the actual insulin sensitivity impairment. Thus, first aim of the study was exploring in pregnancy the relationships between TyG and OGTT-derived insulin sensitivity. In addition, we developed a new version of TyG, for improved performance as marker of insulin resistance in pregnancy.

Methods

At early pregnancy, a cohort of 109 women underwent assessment of maternal biometry and blood tests at fasting, for measurements of several variables (visit 1). Subsequently (26 weeks of gestation) all visit 1 analyses were repeated (visit 2), and a subgroup of women (84 selected) received a 2 h-75 g OGTT (30, 60, 90, and 120 min sampling) with measurement of blood glucose, insulin and C-peptide for reliable assessment of insulin sensitivity (PREDIM index) and insulin secretion/beta-cell function. The dataset was randomly split into 70% training set and 30% test set, and by machine learning approach we identified the optimal model, with TyG included, showing the best relationship with PREDIM. For inclusion in the model, we considered only fasting variables, in agreement with TyG definition.

Results

The relationship of TyG with PREDIM was weak. Conversely, the improved TyG, called TyGIS, (linear function of TyG, body weight, lean body mass percentage and fasting insulin) resulted much strongly related to PREDIM, in both training and test sets (R² > 0.64, p < 0.0001). Bland–Altman analysis and equivalence test confirmed the good performance of TyGIS in terms of association with PREDIM. Different further analyses confirmed TyGIS superiority over TyG.

Conclusions

We developed an improved version of TyG, as new surrogate marker of insulin sensitivity in pregnancy (TyGIS). Similarly to TyG, TyGIS relies only on fasting variables, but its performances are remarkably improved than those of TyG.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01649-8.

Periconceptional and First Trimester Ultraprocessed Food Intake and Maternal Cardiometabolic Outcomes

OBJECTIVE

Ultraprocessed foods (UPFs) have been linked with obesity and cardiometabolic diseases in the general population but are understudied in pregnancy. We examined associations of UPF intake with gestational weight gain (GWG), glycemic, and blood pressure outcomes in pregnancy.

RESEARCH DESIGN AND METHODS

Pregnant women (n = 1,948) in a prospective U.S. cohort self-reported the past 3-month diet using a food frequency questionnaire (FFQ) at 8-13 weeks of gestation. The intake quantity (g/day) of foods and beverages identified as UPFs was ranked into quartiles. Associations of UPFs were evaluated, after adjusting for confounders, with 2nd and 3rd trimester Institute of Medicine (IOM) GWG categories, gestational diabetes mellitus (GDM), and hypertensive disorders of pregnancy (GHTN). Secondary outcomes included GWG rate, glucose challenge test 1-h glucose, and blood pressure trajectories from linear mixed models.

RESULTS

A total of 492 (25.2%) and 699 women (35.9%) had 2nd and 3rd trimester excessive GWG, respectively, and 85 women (4.4%) had GDM and 63 (3.2%) had severe hypertension or preeclampsia. UPF intake was not associated with higher odds of excessive GWG (quartile 4 vs. 1: adjusted odds ratio 0.68 [95% CI 0.44, 1.05], P-trend = 0.10 for 2nd trimester) or GDM risk (quartile 4 vs. 1: adjusted risk ratio 0.99 [95% CI 0.46, 2.11], P-trend = 0.85). Although UPF intake was positively associated with minor differences blood pressure trajectories, associations with GHTN were null.

CONCLUSIONS

The expected unfavorable association of higher UPF intake with excessive GWG, GDM, and GHTN was not observed in our cohort of low-risk pregnant women. These results are based on a limited sample size and require replication.

Maternal Glycemic Spectrum and Adverse Pregnancy and Perinatal Outcomes in a Multiracial US Cohort

Diabetes mellitus (pregestational (PDM) and gestational (GDM)) is associated with adverse pregnancy outcomes (APOs). However, studies exploring the association of APOs with maternal glycemia among women without PDM/GDM are limited. We utilized data from 4119 women (307-PDM; 582-GDM; 3230-non-PDM/GDM) in the Boston Birth Cohort (1998-2016). Women in the non-PDM/GDM group were subdivided by tertiles of 1 h, 50 g oral glucose load test at 24-32 weeks: T1: 50-95 mg/dL (n = 1166), T2: 96-116 mg/dL (n = 1151), T3: 117-201 mg/dL (n = 913). Using multivariable logistic regression, we examined the association of maternal glycemia with APOs-preterm birth (PTB) and hypertensive disorders of pregnancy (HDP)-and adverse perinatal outcomes-high birth weight (HBW), cesarean section (CS), and sub-analyses by race-ethnicity. Compared to women in T1, women in T2 and T3 had a higher prevalence of pre-existing hypertension (T1: 2.8% vs. T2: 5.2% vs. T3: 6.3%) and obesity (T1: 13.3% vs. T2: 18.1% vs. T3: 22.9%). Women in T2 and T3 had higher odds of HBW (adjusted odds ratio aOR T2: 1.47 [1.01-2.19] T3: 1.68 [1.13-2.50]) compared to women in T1. Additionally, women in T2, compared to T1, had higher odds of HDP (aOR 1.44 [1.10-1.88]). Among non-Hispanic Black (NHB) women, those in T2 and T3 had higher odds of HDP compared to T1 (aOR T2 1.67 [1.13-2.51]; T3: 1.68 [1.07-2.62]). GDM and PDM were associated with higher odds of HBW, CS, PTB, and HDP, compared to women in T1. In this predominantly NHB and Hispanic cohort, moderate maternal glycemia without PDM/GDM was associated with higher odds of HBW and HDP, even more strongly among NHB women. If confirmed, a review of current guidelines of glucose screening and risk stratification in pregnancy may be warranted.

Optimising Cardiometabolic Risk Factors in Pregnancy: A Review of Risk Prediction Models Targeting Gestational Diabetes and Hypertensive Disorders

Cardiovascular disease, especially coronary heart disease and cerebrovascular disease, is a leading cause of mortality and morbidity in women globally. The development of cardiometabolic conditions in pregnancy, such as gestational diabetes mellitus and hypertensive disorders of pregnancy, portend an increased risk of future cardiovascular disease in women. Pregnancy therefore represents a unique opportunity to detect and manage risk factors, prior to the development of cardiovascular sequelae. Risk prediction models for gestational diabetes mellitus and hypertensive disorders of pregnancy can help identify at-risk women in early pregnancy, allowing timely intervention to mitigate both short- and long-term adverse outcomes. In this narrative review, we outline the shared pathophysiological pathways for gestational diabetes mellitus and hypertensive disorders of pregnancy, summarise contemporary risk prediction models and candidate predictors for these conditions, and discuss the utility of these models in clinical application.

Maternal hemodynamic changes in gestational diabetes: a prospective case-control study

PURPOSE

The aim of the study is to compare maternal hemodynamic adaptations in gestational diabetes (GDM) versus healthy pregnancies.

METHODS

A prospective case-control study was conducted, comparing 69 singleton pregnancies with GDM and 128 controls, recruited between September 2018 and April 2019 in Maternal-Fetal Medicine Unit, Careggi University Hospital, Florence, Italy. Hemodynamic assessment by UltraSonic Cardiac Output Monitor (USCOM) was performed in both groups in four gestational age intervals: 17-20 weeks (only in early GDM cases), 26-30 weeks, 32-35 weeks and 36-39 weeks. We evaluated six hemodynamic parameters comparing GDM cases versus controls: cardiac output (CO), cardiac index (CI), stroke volume (SV), total vascular resistance (TVR), inotropy index (INO) and potential to kinetic energy ratio (PKR).

RESULTS

GDM group had significantly lower values of CO and SV than controls from the early third trimester (26-30 weeks) until term (p < 0.001). CI is significantly lower in GDM women already at the first evaluation (p = 0.002), whereas TVR and PKR were significantly higher in GDM (p < 0.001). GDM women showed also lower INO values than controls in all assessments.

CONCLUSIONS

A hemodynamic maternal maladaptation to pregnancy can be detected in GDM women. The effect of hyperglycemia on vascular system or a poor pre-pregnancy cardiovascular (CV) reserve could explain this hemodynamic maladaptation. The abnormal CV response to pregnancy in GDM women may reveal a predisposition to develop CV disease later in life and might help in identifying patients who need a CV follow-up.

Revisiting Regulators of Human β-cell Mass to Achieve β-cell-centric Approach Toward Type 2 Diabetes

Type 2 diabetes (T2DM) is characterized by insulin resistance and β-cell dysfunction. Because patients with T2DM have inadequate β-cell mass (BCM) and β-cell dysfunction worsens glycemic control and makes treatment difficult, therapeutic strategies to preserve and restore BCM are needed. In rodent models, obesity increases BCM about 3-fold, but the increase in BCM in humans is limited. Besides, obesity-induced changes in BCM may show racial differences between East Asians and Caucasians. Recently, the developmental origins of health and disease hypothesis, which states that the risk of developing noncommunicable diseases including T2DM is influenced by the fetal environment, has been proposed. It is known in rodents that animals with low birthweight have reduced BCM through epigenetic modifications, making them more susceptible to diabetes in the future. Similarly, in humans, we revealed that individuals born with low birthweight have lower BCM in adulthood. Because β-cell replication is more frequently observed in the 5 years after birth, and β cells are found to be more plastic in that period, a history of childhood obesity increases BCM. BCM in patients with T2DM is reduced by 20% to 65% compared with that in individuals without T2DM. However, since BCM starts to decrease from the stage of borderline diabetes, early intervention is essential for β-cell protection. In this review, we summarize the current knowledge on regulatory factors of human BCM in health and diabetes and propose the β-cell–centric concept of diabetes to enhance a more pathophysiology-based treatment approach for T2DM.

Associations between insulin resistance and adverse pregnancy outcomes in women with gestational diabetes mellitus: a retrospective study

Background

This study aimed to explore the relationship between insulin resistance (IR) and adverse pregnancy outcomes in women with gestational diabetes mellitus (GDM), and to determine the risk factors for IR in women with GDM.

Methods

This study employed a retrospective survey of 710 women diagnosed with GDM. Serum lipids, fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1c), and serum protein were measured in the first trimester (6–12 weeks), and OGTT and fasting insulin tests were performed in the second trimester (24–28 weeks). These results were then used to evaluate IR by homeostasis model assessment (HOMA). When HOMA-IR ≥ 2.0, IR was diagnosed. The relationship between HOMA-IR and adverse pregnancy outcomes was analyzed by a logistic regression model, and multiple stepwise regression was used to analyze the risk factors of IR.

Results

IR significantly increasd the risk of the hypertensive disorders of pregnancy and large for gestational age (LGA) (OR = 5.31,95%CI:1.87,15.10; OR = 1.65,95%CI:1.10, 2.48, respectively) in women with GDM, but not for cesarean section, premature delivery, premature rupture of membranes, postpartum hemorrhage, macrosomia and SGA. Compared to normal groups, greater body mass index (BMI) before pregnancy category (overweight or obesity group) were associated with higher risk of IR in the second trimester, the OR (95% CI) were 4.09 (2.65, 6.30) and 6.52 (2.99, 14.20). And higher level of FPG (OR = 1.63, 95%CI: 1.11, 2.40), TG (OR = 1.32, 95%CI: 1.08, 1.63) and weight gain before diagnosis of GDM (OR = 1.08, 95%CI: 1.02, 1.15) were also associated with higher risk of IR in the second trimester in women with GDM, while age (OR = 0.94, 95%CI: 0.90, 0.98)was the weak protective factor for IR.

Conclusion

GDM with IR in the second trimester increased adverse pregnancy outcomes, especially the risk of hypertensive disorders of pregnancy and LGA. In addition, FPG, HbA1c, and TG in early pregnancy, pre-pregnant BMI and weight gain before diagnosis of GDM were all independent risk factors for IR.

A Narrative Review of Placental Contribution to Adverse Pregnancy Outcomes in Women With Polycystic Ovary Syndrome

CONTEXT

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy of reproductive-aged women. In pregnancy, women with PCOS experience increased risk of miscarriage, gestational diabetes, preeclampsia, and extremes of fetal birth weight, and their offspring are predisposed to reproductive and cardiometabolic dysfunction in adulthood. Pregnancy complications, adverse fetal outcomes, and developmental programming of long-term health risks are known to have placental origins. These findings highlight the plausibility of placental compromise in pregnancies of women with PCOS.

EVIDENCE SYNTHESIS

A comprehensive PubMed search was performed using terms "polycystic ovary syndrome," "placenta," "developmental programming," "hyperandrogenism," "androgen excess," "insulin resistance," "hyperinsulinemia," "pregnancy," and "pregnancy complications" in both human and animal experimental models.

CONCLUSIONS

There is limited human placental research specific to pregnancy of women with PCOS. Gestational androgen excess and insulin resistance are two clinical hallmarks of PCOS that may contribute to placental dysfunction and underlie the higher rates of maternal-fetal complications observed in pregnancies of women with PCOS. Additional research is needed to prevent adverse maternal and developmental outcomes in women with PCOS and their offspring.

Expression profile of circular RNAs in placentas of women with gestational diabetes mellitus

Forty-five pregnant women who underwent cesarean section, including 30 cases of gestational diabetes mellitus (GDM) and 15 normal pregnant women, were enrolled in this study to examine the differential expression of circular RNAs (circRNAs) in the placentas of women with GDM by RNA sequencing (RNA-seq) analysis. The differentially expressed circRNAs were analyzed bioinformatically using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and circRNA-microRNA (miRNA) interaction prediction. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the results. A total of 8,321 circRNAs were identified in the human placenta, among which 46 were differentially expressed (fold change ≥2 and p < 0.05), including three that were upregulated and 43 that were downregulated. According to the GO and KEGG enrichment results, these circRNAs may be associated with vital biological processes, cellular components, molecular functions, and signaling pathways. In particular, KEGG analysis shown they may be involved in advanced glycation end products-receptor for advanced glycation end products (AGE-RAGE) signaling pathway in diabetic complications, indicating that these circRNAs might participate in the occurrence and pathogenesis of GDM. qRT-PCR verified that the expression of circ_5824, circ_3636, and circ_0395 was consistent with RNA-seq analysis; their expression levels were significantly lower in the GDM group than in the control group. The circRNA-miRNA interaction was analyzed according to the molecular sponge mechanism, and its potential function is discussed. These results shed light on future functional studies of circRNAs related to GDM.

Skeletal muscle as a protagonist in the pregnancy metabolic syndrome

The pregnant woman normally shows clinical manifestations similar to a metabolic syndrome (MS), due to her metabolic and hemodynamic adaptations in order to share nutrients with the child. If those adjustments are surpassed, a kind of pregnancy MS (PregMS) could appear, characterized by excessive insulin resistance and vascular maladaptation. Skeletal muscle (SKM) must be a protagonist in the PregMS: SKM strength and mass have been associated inversely with MS incidence in non-pregnant patients, and in pregnant women muscular activity modulates metabolic and vascular adaptations that favor better outcomes. Of note, a sedentary lifestyle affects exactly in the other way. Those effects may be explained not only by the old paradigm of SKM being a great energy consumer and store, but because it is an endocrine organ whose chronic activity or deconditioning correspondingly releases myokines modulating insulin sensitivity and cardiovascular adaptation, by direct or indirect mechanisms not well understood. In this document, we present evidence to support the concept of a PregMS and hypothesize on the role of the SKM mass, fiber types composition and myokines in its pathophysiology. Also, we discuss some exercise interventions in pregnancy as a way to test our hypotheses.

Mothers with HIP - The short term and long-term impact, what is new?

Hyperglycemia is one of the most common medical conditions that women encounter during pregnancy and it is due to gestational diabetes (GDM) in the majority of cases (International Diabetes Federation, 2015) [1]. GDM is associated with a higher incidence of maternal morbidity in pregnancy in term of hypertensive disorders/preclampsia and higher rate of cesarean delivery but also with long-term risk of type 2 diabetes and cardiovascular disease. Pregnancy can therefore be considered a stress test; diagnosis of HIP can unmask a preexisting susceptibility and consequently a future risk for type 2 diabetes and can be a useful marker of future cardiovascular risk. Postpartum follow up provides an excellent opportunity to implement healthy lifestyle behaviors to prevent or delay the development of diabetes or cardiovascular disease. The aim of the current review is to focus on short and long term maternal morbidity of HIP.

miR-335-5p induces insulin resistance and pancreatic islet β-cell secretion in gestational diabetes mellitus mice through VASH1-mediated TGF-β signaling pathway

Multiple studies have reported different methods in treating gestational diabetes mellitus (GDM); however, the relationship between miR-335-5p and GDM still remains unclear. Here, this study explores the effect of miR-335-5p on insulin resistance and pancreatic islet β-cell secretion via activation of the TGFβ signaling pathway by downregulating VASH1 expression in GDM mice. The GDM mouse model was established and mainly treated with miR-335-5p mimic, miR-335-5p inhibitor, si-VASH1, and miR-335-5p inhibitor + si-VASH1. Oral glucose tolerance test (OGTT) was conducted to detect fasting blood glucose (FBG) fasting insulin (FINS). The OGTT was also used to calculate a homeostasis model assessment of insulin resistance (HOMA-IR). A hyperglycemic clamp was performed to measure the glucose infusion rate (GIR), which estimated β-cell function. Expressions of miR-335-5p, VASH1, TGF-β1, and c-Myc in pancreatic islet β-cells were determined by RT-qPCR, western blot analysis, and insulin release by ELISA. The miR-335-5p mimic and si-VASH1 groups showed elevated blood glucose levels, glucose area under the curve (GAUC), and HOMA-IR, but a reduced GIR and positive expression of VASH1. Overexpression of miR-335-5p and inhibition of VASH1 contributed to activated TGFβ1 pathway, higher c-Myc, and lower VASH1 expressions, in addition to downregulated insulin and insulin release levels. These findings provided evidence that miR-335-5p enhanced insulin resistance and suppressed pancreatic islet β-cell secretion by inhibiting VASH1, eventually activating the TGF-β pathway in GDM mice, which provides more clinical insight on the GDM treatment.

ELABELA plasma concentrations are increased in women with late-onset preeclampsia

Objective: ELABELA is a newly discovered peptide hormone that appears to be implicated in the mechanisms leading to preeclampsia, independently of angiogenic factors. The aim of the current study was to investigate whether women with early- or late-onset preeclampsia have altered ELABELA plasma concentrations compared to gestational-age-matched normal pregnant women.Methods: This retrospective cross-sectional study focused on the maternal plasma samples collected from 232 women with a singleton pregnancy who were allocated into the following groups: (1) early-onset preeclampsia (<34 weeks of gestation, N = 56); (2) late-onset preeclampsia (≥34 weeks of gestation, N = 57); and (3) gestational-age-matched controls with a normal pregnancy [(<34 weeks of gestation, N = 59); (≥34 weeks of gestation, N = 60)]. ELABELA plasma concentrations were determined using a validated enzyme immunoassay.Results: (1) ELABELA plasma concentrations are higher in patients with late-onset preeclampsia compared with those from gestational-age-matched controls with a normal pregnancy [median: 7.99 ng/mL (IQR, 5.3-13.95 ng/mL) versus median: 4.17 ng/mL (IQR, 3-11.19 ng/mL), p =.001]; (2) ELABELA plasma concentrations in patients with early-onset preeclampsia do not differ from those of normal pregnant women [median: 6.09 ng/mL (IQR, 2.8-10.66 ng/mL) versus median: 4.02 ng/mL (IQR, 3.26-7.49), p = .32]; and (3) ELABELA plasma concentrations are higher in patients with late-onset preeclampsia compared to those with early-onset preeclampsia [median: 7.99 ng/mL (IQR, 5.3-13.95 ng/mL) versus median: 6.09 ng/mL (IQR, 2.8-10.66 ng/mL), p = .01].Conclusion: ELABELA plasma concentrations are higher in patients with late-onset preeclampsia than in those with a normal pregnancy. However, women with early-onset preeclampsia have similar ELABELA plasma concentrations to those with a normal pregnancy. These findings provide insight into the ELABELA axis during the human syndrome of preeclampsia. In addition, these data support the concept that different pathophysiologic mechanisms are implicated in early- and late-onset preeclampsia.

Associations between bacterial infections and blood pressure in pregnancy

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Antibiotic use in pregnancy was associated with a 2–3 mmHg rise in blood pressure.

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It was related more to changes in diastolic than systolic blood pressure.

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The most likely cause is exposure to bacterial infections.

Objectives

To test the hypothesis that bacterial infections in pregnancy are related to maternal blood pressure.

Study design

Bacterial infection was assessed using antibiotic usage as a surrogate and its association with blood pressure in pregnancy tested in the Cambridge Baby Growth Study.

Main outcome measures

Antibiotic usage in pregnancy was self-reported in questionnaires. Blood pressure measurements at four time points in pregnancy were collected from the hospital notes of 622 women.

Results

Using all the available blood pressure readings (adjusted for weeks gestation) antibiotic usage was associated with a higher mean arterial blood pressure across pregnancy: antibiotics used 85 (84, 87) mmHg vs. no antibiotics used 83 (83, 84) mmHg (β = 2.3 (0.6, 4.0) mmHg, p = 9.6 × 10⁻³, from 621 individuals). Further analysis revealed that antibiotic usage was associated with diastolic (β = 2.3 (0.6, 4.0) mmHg; p = 7.0 × 10⁻³) more than systolic blood pressure (β = 1.4 (−0.9, 3.7) mmHg; p = 0.2). The effect size associated with antibiotic usage appeared to rise slightly after the first trimester.

Conclusions

Bacterial infection in pregnancy, as assessed by self-reported antibiotic usage, is associated with small rises in blood pressure.

The prediction of late-onset preeclampsia: Results from a longitudinal proteomics study

BACKGROUND

Late-onset preeclampsia is the most prevalent phenotype of this syndrome; nevertheless, only a few biomarkers for its early diagnosis have been reported. We sought to correct this deficiency using a high through-put proteomic platform.

METHODS

A case-control longitudinal study was conducted, including 90 patients with normal pregnancies and 76 patients with late-onset preeclampsia (diagnosed at ≥34 weeks of gestation). Maternal plasma samples were collected throughout gestation (normal pregnancy: 2-6 samples per patient, median of 2; late-onset preeclampsia: 2-6, median of 5). The abundance of 1,125 proteins was measured using an aptamers-based proteomics technique. Protein abundance in normal pregnancies was modeled using linear mixed-effects models to estimate mean abundance as a function of gestational age. Data was then expressed as multiples of-the-mean (MoM) values in normal pregnancies. Multi-marker prediction models were built using data from one of five gestational age intervals (8-16, 16.1-22, 22.1-28, 28.1-32, 32.1-36 weeks of gestation). The predictive performance of the best combination of proteins was compared to placental growth factor (PIGF) using bootstrap.

RESULTS

1) At 8-16 weeks of gestation, the best prediction model included only one protein, matrix metalloproteinase 7 (MMP-7), that had a sensitivity of 69% at a false positive rate (FPR) of 20% (AUC = 0.76); 2) at 16.1-22 weeks of gestation, MMP-7 was the single best predictor of late-onset preeclampsia with a sensitivity of 70% at a FPR of 20% (AUC = 0.82); 3) after 22 weeks of gestation, PlGF was the best predictor of late-onset preeclampsia, identifying 1/3 to 1/2 of the patients destined to develop this syndrome (FPR = 20%); 4) 36 proteins were associated with late-onset preeclampsia in at least one interval of gestation (after adjustment for covariates); 5) several biological processes, such as positive regulation of vascular endothelial growth factor receptor signaling pathway, were perturbed; and 6) from 22.1 weeks of gestation onward, the set of proteins most predictive of severe preeclampsia was different from the set most predictive of the mild form of this syndrome.

CONCLUSIONS

Elevated MMP-7 early in gestation (8-22 weeks) and low PlGF later in gestation (after 22 weeks) are the strongest predictors for the subsequent development of late-onset preeclampsia, suggesting that the optimal identification of patients at risk may involve a two-step diagnostic process.

Maternal childhood cardiometabolic risk factors and pregnancy complications

PURPOSE

The influence of childhood health on later-life health outcomes is increasingly hypothesized but rarely tested. We examined the relationship between cardiometabolic indicators in childhood and risk of pregnancy-induced hypertension, preeclampsia, and gestational diabetes.

METHODS

Childhood measurements from 755 women in the Bogalusa Heart Study included body mass index, systolic and diastolic blood pressure (SBP and DBP), low- and high-density lipoprotein cholesterol, total cholesterol, triglycerides, insulin, and glucose. Average childhood values were estimated by area under the curve computed from longitudinal quadratic random-effects growth models to account for the unequally spaced repeated measures. Women reported pregnancy complications, and medical records were linked to interview data where possible. Log-Poisson models predicted adjusted risk associated with an interquartile range increase in cardiometabolic indicators.

RESULTS

Elevated childhood insulin was associated with 10%-15% increased risk across the three outcomes. Elevated childhood SBP was associated with preeclampsia (SBP RR = 1.50, 95% CI: 1.13, 2.01) and SBP, DBP, and body mass index predicted pregnancy-induced hypertension (SBP RR = 2.15, 95% CI: 1.65, 2.82; DBP RR = 1.83, 95% CI: 1.38, 2.43; BMI RR = 1.67, 95% CI: 1.41, 1.98). Blood pressure mediated the association between childhood body mass index and pregnancy-induced hypertension.

CONCLUSIONS

Results suggest the potential long-term impact of early-life cardiometabolic profiles on complications of pregnancy.

Clinical study on the association between pregnancy-induced hypertension and insulin resistance

The aim of the present study was to explore the association between pregnancy-induced hypertension (PIH) and insulin resistance (IR). A total of 50 cases of PIH and 50 healthy pregnant women with a similar gestational age were enrolled. The hyperinsulinemic-euglycemic clamp technique was used to evaluate the degree of IR and all 100 subjects were divided into an IR and a non-IR group accordingly. Subsequently, the correlation between the systolic or diastolic blood pressure was assessed; furthermore, a homeostasis model assessment of IR (HOMA-IR), a HOMA of the insulin sensitivity index (HOMA-ISI) and a HOMA of β cell function (HOMA-β%) were performed. Moreover, the effect of IR on PIH was assessed and the protein expression of insulin receptor substrate (IRS)-1, phosphorylated (p)-IRS-1, AKT and p-AKT were detected in the placental plasma by western blot analysis. The results showed that in the PIH group, the p-IRS-1/IRS-1 and p-AKT/AKT ratios were decreased compared with those in the control group. Blood flow parameters, including perfusion index, retinal resistive index and systolic maximum velocity/end-diastolic velocity ratio in the IR group were higher, while time averaged velocity was lower compared with that in the non-IR group. Furthermore, the HOMA-ISI and HOMA-β% were decreased, while the HOMA-IR was increased in the PIH group compared to that in the control group; alongside the blockage of the insulin signaling pathway, these factors may therefore cause PIH. The present study may provide novel therapeutic approaches for PIH.

The effects of progressive muscular relaxation and breathing control technique on blood pressure during pregnancy

Background:

Hypertensive disorders in pregnancy are the main cause of maternal and fetal mortality; however, they have no definite effective treatment. The researchers aimed to study the effects of progressive muscular relaxation and breathing control technique on blood pressure (BP) during pregnancy.

Materials and Methods:

This three-group clinical trial was conducted in Mashhad health centers and governmental hospitals. Sixty pregnant (after 20 weeks of gestational age) women with systolic BP ≥ 135 mmHg or diastolic BP ≥ 85 mmHg were assigned to three groups. Progressive muscular relaxation and breathing control exercises were administered to the two experimental groups once a week in person and in the rest of the days by instructions given on a CD for 4 weeks. BP was checked before and after the interventions. BP was measured before and after 15 min subjects' waiting without any especial intervention in the control group.

Results:

After 4 weeks of intervention, the systolic (by a mean of 131.3 to 117.2, P = 0.001 and by a mean of 131.05 to 120.5, P = 0.004, respectively) and diastolic (by a mean of 79.2 to 72.3, P = 0.001 and by a mean of 80.1 to 76.5, P = 0.047, respectively) BPs were significantly decreased in progressive muscular relaxation and breathing control groups, but they were not statistically significant in the control group.

Conclusions:

The interventions were effective on decreasing systolic and diastolic BP to normal range after 4 weeks in both the groups. The effects of both the interventions were more obvious on systolic BP compared to diastolic BP.

Fetal programming of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects up to 6.8% of reproductive age women. Experimental research and clinical observations suggest that PCOS may originate in the very early stages of development, possibly even during intrauterine life. This suggests that PCOS is either genetically-transmitted or is due to epigenetic alterations that develop in the intrauterine microenvironment. Although familial cases support the role of genetic factors, no specific genetic pattern has been defined in PCOS. Several candidate genes have been implicated in its pathogenesis, but none can specifically be implicated in PCOS development. Hypotheses based on the impact of the intrauterine environment on PCOS development can be grouped into two categories. The first is the "thrifty" phenotype hypothesis, which states that intrauterine nutritional restriction in fetuses causes decreased insulin secretion and, as a compensatory mechanism, insulin resistance. Additionally, an impaired nutritional environment can affect the methylation of some specific genes, which can also trigger PCOS. The second hypothesis postulates that fetal exposure to excess androgen can induce changes in differentiating tissues, causing the PCOS phenotype to develop in adult life. This review aimed to examine the role of fetal programming in development of PCOS.

Favorable effects of vitamin D supplementation on pregnancy outcomes in gestational diabetes: a double blind randomized controlled clinical trial

Gestational diabetes mellitus (GDM) has been recognized as a significant risk factor for unfavorable pregnancy outcomes. Prevalence of vitamin D deficiency is highly prevalent among women with GDM. This study was designed to assess the effect of vitamin D supplementation on pregnancy outcomes of pregnant women with GDM who were not on oral hypoglycemic agents. This randomized controlled clinical trial was performed among 45 pregnant women diagnosed with GDM at 24-28 weeks' gestation. Subjects were randomly assigned to consume either vitamin D supplements (cholecalciferol) or placebo. Individuals in the vitamin D group (n=22) received 50 000 IU vitamin D3 pearl 2 times during the study: at study baseline and day 21 of intervention and those in placebo group (n=23) received 2 placebos at the mentioned times. Fasting blood samples were taken at baseline to measure fasting plasma glucose. Participants underwent a 3-h oral glucose tolerance tests (OGTT) and the blood samples were collected at time 60, 120, and 180 min to measure plasma glucose levels. Newborn's weight, height, head circumference, Apgar score, and hyperbilirubinemia were determined. Taking vitamin D supplements, compared with placebo, resulted in improved pregnancy outcomes; such that those in the vitamin D group had no case of polyhydramnios, while 17.4% of subjects in placebo group had this condition (p=0.04). In addition, newborn's hyperbilirubinemia was significantly lower in vitamin D group than that in placebo group (27.3% vs. 60.9%, p=0.02). In conclusion, vitamin D supplementation for 6 weeks among pregnant women with GDM resulted in decreased maternal polyhydramnios and infant hyperbilirubinemia compared with placebo. Clinical trial registration number www.irct.ir:IRCT201305115623N7.

Preeclampsia and diabetes

Preeclampsia is diagnosed in women presenting with new onset hypertension accompanied by proteinuria or other signs of severe organ dysfunction in the second half of pregnancy. Preeclampsia risk is increased 2- to 4-fold among women with type 1 or type 2 diabetes. The limited number of pregnant women with preexisting diabetes and the difficulties associated with diagnosing preeclampsia in women with proteinuria prior to pregnancy are significant barriers to research in this high-risk population. Gestational diabetes mellitus (GDM) also increases preeclampsia risk, although it is unclear whether these two conditions share a common pathophysiological pathway. Nondiabetic women who have had preeclampsia are more likely to develop type 2 diabetes later in life. Among women with type 1 diabetes, a history of preeclampsia is associated with an increased risk of retinopathy and nephropathy. More research examining the pathophysiology, treatment, and the long-term health implications of preeclampsia among women with preexisting and gestational diabetes is needed.

Dopamine D₄ receptors inhibit proliferation and migration of vascular smooth muscle cells induced by insulin via down-regulation of insulin receptor expression

Vascular smooth muscle cells (VSMCs) proliferation and migration, which are central in the development of vascular diseases, are regulated by numerous hormones and humoral factors. Activation of the insulin receptor stimulates VSMCs proliferation while dopamine receptors, via D₁ and D₃ receptors, inhibit the stimulatory effects of norepinephrine on VSMCs proliferation. We hypothesize that activation of the D₄ dopamine receptor may also inhibit the proliferation and migration of VSMCs, therefore, inhibit atherosclerosis. Our current study found that insulin increased the proliferation and migration of A10 cells, an effect that was reduced in the presence of a D₄ receptor agonist, PD168077. The negative effect of the D₄ receptor on insulin’s action may be via decreasing insulin receptor expression, because activation of the D₄ receptor inhibited insulin receptor protein and mRNA expressions, indicating that the regulation occured at the transcriptional or post-transcriptional levels. To determine whether or not the inhibition of D₄ receptor on insulin-mediated proliferation and migration of VSMCs has physiological significance, hyper-insulinemic Sprague–Dawley rats with balloon-injured carotid artery were treated with a D₄ agonist, PD168077, (6 mg/kg/d) for 14 days. We found that PD168077 significantly inhibited neointimal formation by inhibition of VSMC proliferation. This study suggests that activation of the D₄ receptor suppresses the proliferation and migration of VSMCs, therefore, inhibit atherosclerosis. The D₄ receptor may be a potential therapeutic target to reduce the effects of insulin on artery remodeling.

Maternal serum resistin at 11 to 13 weeks' gestation in normal and pathological pregnancies

The objective was to examine maternal serum levels of resistin at 11 to 13 weeks' gestation in normal and pathological pregnancies. Serum resistin, pregnancy-associated plasma protein A (PAPP-A), and uterine artery pulsatility index (PI) at 11 to 13 weeks were measured in 480 singleton pregnancies, including 240 with normal outcome, 60 that subsequently developed preeclampsia (PE), 60 that developed gestational diabetes mellitus (GDM), 60 that delivered large for gestational age (LGA) neonates, and 60 that delivered small for gestational age (SGA) neonates. Each value in both the normal and pathological outcome groups was expressed as a multiple of the expected normal median (MoM), and the median MoM values in the outcome groups were compared. In the PE group, compared with the controls, there were an increase in median resistin (1.22 MoM, P = .003) and uterine artery PI (1.25 MoM, P < .0001) and a decrease in serum PAPP-A (0.72, P < .0001). There was no significant association between serum resistin with either uterine artery PI (P = .415) or serum PAPP-A (P = .290). In the SGA, LGA, and GDM groups, serum resistin MoM was not significantly different from that of the controls (P = .415, P = .702, and P = .549, respectively). In pregnancies that develop PE, maternal serum resistin concentration at 11 to 13 weeks is increased in a manner not related to altered placental perfusion or function. In pregnancies complicated by the development of GDM or delivery of SGA or LGA neonates, serum resistin is not significantly altered.

Adipokines: new emerging roles in fertility and reproduction

Adipose tissue is a specialized endocrine and paracrine organ producing specific factors called adipokines. It is well known that adipokines balance is fundamental to prevent obesity, metabolic syndrome, and cardiovascular diseases. During the last years, new roles of adipokines have been emerging in the field of fertility and reproduction. Although the literature is still quite controversial, this review serves to resume current knowledge on this topic. Alterations in adipokine levels or in their mechanism of action are associated with fertility impairment and pregnancy diseases, as well as with obesity, metabolic syndrome, and cardiovascular diseases. Normal levels of adipokines are fundamental to maintain integrity of hypothalamus-pituitary-gonadal axis, regular ovulatory processes, successful embryo implantation, and physiologic pregnancy. More efforts are needed to understand the mechanisms and to the extent to which adipokine changes are involved in the impairment of fertility and pregnancy outcome, to find possible medical treatments.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this educational activity, the obstetrician/gynecologist should be better able to demonstrate current knowledge in the research field of adipokines in fertility and reproduction; evaluate the central role of metabolism balance in good pregnancy outcome; and apply new perspectives of studies.

Evaluating the extent of pregravid risk factors of gestational diabetes mellitus in women in tehran

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with maternal and fetal complications. Specific outcomes in previous pregnancies are considered as risk factors for GDM in the consecutive pregnancies. The aim of this study was to evaluate the pregravid risk factors of GDM in multigravid women.

METHODS

We conducted a retrospective cross sectional study on 114 multigravid women with GDM without previous history of diabetes and compared them with non-diabetic controls. We used modified criteria of Carpenter and Coustan for screening. Risk factors were obtained from medical records of individuals.

RESULTS

We found that women of 26 years and older who had previous neonates with birth weight more than 3800 gram and those affected with hypothyroidism or chronic hypertension were at risk for GDM. The difference of the number of preterm birth in GDM women and healthy controls was statistically significant (p=0.05). There was no significant difference between the numbers of pregnancies, parity, previous fetal and neonatal death and abortion number between patients and the control group.

CONCLUSION

Our results show that maternal age over 26 years, birth weight of previous neonate more than 3800 g, hypothyroidism, chronic hypertension and probably history of preterm birth are significant risk factors for GDM.

Brick by brick: metformin for gestational diabetes mellitus?

Evaluation of: Balani J, Hyer SL, Rodin DA, Shehata H. Pregnancy outcomes in women with gestational diabetes treated with metformin or insulin: a case-control study. Diabet. Med. 26(8), 798-802 (2009). This paper reviews a case-control study, reported by Balani et al., comparing maternal and neonatal outcomes of women treated for gestational diabetes mellitus with either metformin or insulin. A cohort of 100 women treated with metformin alone, without insulin rescue, was compared with a retrospective cohort of 100 women treated with insulin. Results favored metformin. This paper discusses issues related to the safety and efficiency of metformin treatment during pregnancy, the attitudes of pregnant women toward treatment options, public health policy and the worldwide gestational diabetes mellitus epidemic, as well as the financial burden of therapy, particularly for developing countries. It also looks at the pathophysiology of gestational diabetes mellitus and the need for clinical trial assessment of combination oral-hypoglycemic therapy.