Maternal plasma 25-hydroxyvitamin D levels, angiogenic factors, and preeclampsia

Maternal angiogenic factor disruptions prior to clinical diagnosis of preeclampsia: insights from the REVAMP study

Preeclampsia is characterized by impaired angiogenesis and assessment of angiogenic factors can play a crucial role in the early diagnosis of preeclampsia. The current study reports the levels of angiogenic factors longitudinally from early pregnancy in women with preeclampsia and in the subtypes of preeclampsia, to identify their role in early prediction of preeclampsia. A total of 1154 women with singleton pregnancies were recruited in early pregnancy from 2 hospitals. Blood samples were collected, plasma samples were separated and stored at four time points across gestation: V1 = 11-14 weeks, V2 = 18-22 weeks, V3 = 26-28 weeks, and V4 = at delivery. The current study includes a total of 108 women developed preeclampsia (PE), and 216 matched controls. Angiogenic factors were estimated using commercially available ELISA kits. Receiver operating characteristic (ROC) curves were used to evaluate the potential diagnostic value in the prediction of PE. Lower levels of VEGF, PlGF, and higher levels of sEng and sEng/PlGF ratio (p < 0.05 for all) predate clinical diagnosis in women with preeclampsia. sEng levels and sEng/PlGF ratio showed significant correlation with odds of preeclampsia at all the timepoints. This study identifies a cut off of 33.5 for sFlt-1/PlGF and 25.9 for sEng/PlGF for prediction of early onset preeclampsia. This study reports various angiogenic factors serially across gestation in a general population to identify women at risk of developing preeclampsia and its subtypes. The study also reports a potential biomarker and a pragmatic window for estimation of angiogenic markers to identify women at risk.

Vitamin D supplementation modulates glycated hemoglobin (HBA1c) in diabetes mellitus

Diabetes is a metabolic illness that increases protein glycosylation in hyperglycemic conditions, which can have an impact on almost every organ system in the body. The role of vitamin D in the etiology of diabetes under RAGE (receptor for advanced glycation end products) stress has recently received some attention on a global scale. Vitamin D's other skeletal benefits have generated a great deal of research. Vitamin D's function in the development of type 1 and type 2 diabetes is supported by the discovery of 1,25 (OH)2D3 and 1-Alpha-Hydroylase expression in immune cells, pancreatic beta cells, and several other organs besides the bone system. A lower HBA1c level, metabolic syndrome, and diabetes mellitus all seems to be associated with vitamin D insufficiency. Most of the cross-sectional and prospective observational studies that were used to gather human evidence revealed an inverse relationship between vitamin D level and the prevalence or incidence of elevated HBA1c in type 2 diabetes. Several trials have reported on the impact of vitamin D supplementation for glycemia or incidence of type 2 diabetes, with varying degrees of success. The current paper examines the available data for a relationship between vitamin D supplementation and HBA1c level in diabetes and discusses the biological plausibility of such a relationship.

Evaluation of the angiogenic factors sFlt-1, PlGF, and the sFlt-1/PlGF ratio in preeclampsia and associated features

PROBLEM

Soluble Fms-like tyrosine kinase-1 (sFLT-1) and placental growth factor (PlGF) were previously reported to play a key role in the pathogenesis of preeclampsia (PE). We tested the link between altered PlGF and sFLT-1 levels, and their ratio (sFlt-1/PlGF) with PE and PE-associated featured in Tunisian PE cases and age- and BMI-matched normotensive women.

METHOD OF STUDY

Peripheral blood specimens from 88 women with PE, and 60 control women were tested for PlGF and sFLT by commercially available ELISA.

RESULTS

Significant increases in sFlt-1 levels and in the sFlt-1/PlGF ratio, more than changes in PlGF levels were noted in PE subjects when compared to control women. Elevation in sFlt-1 and sFlt-1/PlGF ratio was observed at different percentile values in PE cases. The receiver operating characteristic (ROC) area under the curve (AUC) for sFlt-1, PlGF, and sFlt-1/PlGF ratio were 0.869 ± 0.031, 0.463 ± 0.048, and 0.759 ± 0.039, respectively. A systematic shift in sFlt-1, but not in PlGF, distributions for higher values occurred in PE subjects. A progressive increase in the adjusted OR paralleled increased sFlt-1 and the sFlt-1/PlGF ratio percentile values; no similar trend was noted for the PlGF percentiles. Increased sFlt-1 levels and sFlt-1/PlGF ratio were significantly correlated with dysmenorrhea, hypertension, baby weight, and C-section. In contrast, no correlation was found between PlGF and the PE-associated features tested.

CONCLUSIONS

Increased sFlt-1 levels and corresponding sFlt-1/PlGF ratio, but not circulating PlGF levels, constitute an independent risk factor for PE.

Unravelling the potential of angiogenic factors for the early prediction of preeclampsia

Preeclampsia is a multisystem, multiorgan hypertensive disorder of pregnancy responsible for maternal and perinatal morbidity and mortality in low- and middle-income countries. The classic diagnostic features hold less specificity for preeclampsia and its associated adverse outcomes, suggesting a need for specific and reliable biomarkers for the early prediction of preeclampsia. The imbalance of pro- and antiangiogenic circulatory factors contributes to the pathophysiology of preeclampsia. Several studies have examined the profile of angiogenic factors in preeclampsia to search for a biomarker that will improve the diagnostic ability of preeclampsia and associated adverse outcomes. This may help in more efficient patient management and the reduction of associated health care costs. This article reviews the findings from previous studies published to date on angiogenic factors and suggests a need to apply a multivariable model from the beginning of pregnancy and continuing throughout gestation for the early and specific prediction of preeclampsia.

Etiopathogenesis, Challenges and Remedies Associated With Female Genital Tuberculosis: Potential Role of Nuclear Receptors

Extra-pulmonary tuberculosis (EPTB) is recognized mainly as a secondary manifestation of a primary tuberculosis (TB) infection in the lungs contributing to a high incidence of morbidity and mortality. The TB bacilli upon reactivation maneuver from the primary site disseminating to other organs. Diagnosis and treatment of EPTB remains challenging due to the abstruse positioning of the infected organs and the associated invasiveness of sample acquisition as well as misdiagnosis, associated comorbidities, and the inadequacy of biomarkers. Female genital tuberculosis (FGTB) represents the most perilous form of EPTB leading to poor uterine receptivity (UR), recurrent implantation failure and infertility in females. Although the number of TB cases is reducing, FGTB cases are not getting enough attention because of a lack of clinical awareness, nonspecific symptoms, and inappropriate diagnostic measures. This review provides an overview for EPTB, particularly FGTB diagnostics and treatment challenges. We emphasize the need for new therapeutics and highlight the need for the exaction of biomarkers as a point of care diagnostic. Nuclear receptors have reported role in maintaining UR, immune modulation, and TB modulation; therefore, we postulate their role as a therapeutic drug target and biomarker that should be explored in FGTB.

Vitamin D, preeclampsia and prematurity: A systematic review and meta-analysis of observational and interventional studies

BACKGROUND

Vitamin D has important functions outside of bone metabolism. Deficiency has been associated with several adverse outcomes during pregnancy such as preeclampsia and prematurity. There is an increasing body of literature on this topic with studies performed to date having produced contradictory results.

OBJECTIVE

To synthesize the literature about vitamin D deficiency and its association with preeclampsia and prematurity in order to determine if maternal vitamin D insufficiency and/or deficiency during pregnancy is associated with the prevalence of preeclampsia and prematurity.

DESIGN

A systematic review and meta-analysis of observational and interventional studies.

METHODS

Two independent researchers reviewed the included studies according to PRISMA reporting guidelines. A protocol for this review was registered in PROSPERO with the registration number: "CRD42019136318". Three electronic databases (PubMed, ScienceDirect and Web of Science); were searched in order to identify eligible studies. Observational and interventional studies were selected which had been published in the last 6 years, and analysed the association between maternal vitamin D concentrations during pregnancy and the development of preeclampsia and/or preterm birth. Data were extracted and presented in tables and figures. Fixed and random-effects meta-analyses were performed on the studies which provided enough sample data to calculate odds ratios. Results from both statistical methods were compared. Meta-analysis cut-off points for vitamin D insufficiency and deficiency were defined as <75nmol/L and <50nmol/L, respectively.

RESULTS

Fifty-five studies met the inclusion criteria. Fixed-effects meta-analysis of the interventional studies indicated that vitamin D supplementation acts as a prevention factor for preeclampsia and prematurity. Fixed-effects meta-analysis of observational studies concluded that vitamin D insufficiency and deficiency are associated with a higher risk of developing preeclampsia. However, prematurity and vitamin D were only associated when maternal vitamin D concentrations was <75 nmol/L. Random-effects meta-analysis found no significant association between vitamin D, preeclampsia and prematurity in either observational or interventional studies.

CONCLUSION

Higher vitamin D concentrations during pregnancy could be associated with a decreased risk of preeclampsia and prematurity but statistical significance of associations depends on the study design used. Well-designed clinical trials with vitamin D supplementation are needed in order to better define associations.

Association of maternal serum 25-hydroxyvitamin D concentrations with risk of preeclampsia: a nested case-control study and meta-analysis

OBJECTIVES

Whether the maternal vitamin D deficiency is associated with preeclampsia is still an argument. We aimed to assess the association between maternal serum 25-hydroxyvitamin D [25(OH)D] concentrations and risk of preeclampsia in a Chinese population and systematically evaluate published evidence on this association.

METHODS

We conducted a nested case-control study involving 122 pregnant women with preeclampsia and 488 pregnant women whose blood pressure was within the normal range (as controls). For further meta-analysis, 20 studies and our study were included for the final pooled analysis, involving 39,031 participants and 3305 preeclampsia cases with various ethnicities.

RESULTS

The results showed that 65.6% of women with preeclampsia had serum 25(OH)D concentrations <50.0 nmol L^-1 compared with 55.3% of women in controls. The 25(OH)D concentrations were significantly lower in women with preeclampsia than controls [Median (IQR), women with preeclampsia versus controls: 43.3 (35.5, 55.2) versus 47.5 (37.6, 60.4) nmol L^-1, p = .014]. For women with 25(OH)D concentrations <50.0 nmol L^-1, they had a 65% increase in preeclampsia risk (95% CI = 1.02-2.69), as compared with women with 25(OH)D concentrations from 50.0 to 74.9 nmol L^-1. Further, meta-analysis showed that low 25(OH)D concentrations were associated with a significantly increased risk of preeclampsia by 62% (pooled OR = 1.62, 95%CI = 1.36-1.94), and the risk effect of low 25(OH)D concentrations existed in most subgroups.

CONCLUSIONS

Low 25(OH)D concentration in pregnancy was significantly associated with preeclampsia risk, and it may serve as biomarkers for the surveillance of high-risk pregnant women.

The role of vitamin D in perinatology. An up-to-date review

The role of vitamin D in perinatology is a subject of major interest in current medicine. There is growing evidence about the role of maternal vitamin D levels in pregnancy outcomes. The aim of this review is to summarize the current literature about the role of vitamin D in perinatology. Evidence from this review suggests associations between low levels of maternal vitamin D and higher risk of certain obstetrical complications. Vitamin D has been found to be related to preeclampsia, gestational diabetes mellitus, low birth weight, and preterm birth. The current literature supports vitamin D supplementation in pregnant women, but more high-quality data are necessary. The problem that remains is how to achieve an optimal 25-hydroxyvitamin D level. To determine the real benefits of vitamin D supplementation in pregnancy, we need high-quality trials in larger groups.

Vitamin D metabolic loci and preeclampsia risk in multi-ethnic pregnant women

Allelic variants in vitamin D metabolism genes may increase the risk of preeclampsia, but few studies have systematically tested this hypothesis. Our objective was to evaluate the relationship between maternal allelic variants in three vitamin D metabolism genes and risk of preeclampsia. Samples were from two case‐control studies of pregnant women who delivered in Pittsburgh, PA from 1999 to 2010 and twelve recruiting sites across the United States from 1959 to 1965. Single‐nucleotide polymorphisms (SNPs) were genotyped 50 kilobases up‐ and down‐stream in three genes (VDR,GC, and CYP27B1) in the samples from both studies, for a total of 744 preeclampsia cases and 2411 controls. Using multivariable logistic regression, we estimated the associations between allelic variation in each locus and preeclampsia risk by maternal race and study. Meta‐analysis was used to estimate the association across race‐study groups for each SNP. Minor allele of a noncoding region of the VDR gene was significantly associated with preeclampsia risk, which was verified in the meta‐analysis [odds ratio (OR), 95% confidence intervals (CI)] after adjusting for multiple comparisons [rs12831006:1.5 (1.2, 2.0), P < 0.0001]. The meta‐analysis identified associations for one intron GC variant [rs843010:1.4 (1.1, 1.9) P < 0.05] and two variants of the flanking region of GC [rs842991:1.5 (1.1, 2.0) P < 0.05; rs16846876:0.75 (0.58, 0.98) P < 0.05]. There were no statistically significant associations for CYP27B1 SNPs. Our results provide additional support for a biological role of vitamin D in preeclampsia.

Vitamin D and risk of preeclampsia: A systematic review and meta-analysis

Introduction

Human vitamin D levels have been increasingly related to a wide range of clinical outcomes. There is a large amount of reports on its associations, especially with obstetric complications, including preeclampsia and gestational diabetes. These results are scarcely consistent and there is still a lack of quality intervention studies to confirm the role of vitamin D in those outcomes. Objective: To review the available scientific evidence on the role of maternal vitamin D in the development of preeclampsia.

Materials and methods

The methodology used followed the recommendations of the Cochrane guide for the preparation of systematic reviews, and for metaanalysis, the Guide of the Metaanalysis of Observational Studies in Epidemiology group (MOOSE). The search included both observational studies and controlled clinical trials.

Results

Low vitamin D levels, measured by the 25-hydroxyvitamin D test, are common in pregnancy. The results of this systematic review and metaanalysis suggest an inverse ratio between vitamin D levels and the development of preeclampsia. There was heterogeneity among the studies with regard to the design, population, geographic location, definitions of exposure, and the outcome. We excluded randomized controlled trials from this meta-analysis.

Conclusion

The inverse association we found suggests that the higher the levels of vitamin D the lesser the probability of developing preeclampsia, in spite of the heterogeneity of the global measurement in this type of analysis.

Systematic Review of Vitamin D and Hypertensive Disorders of Pregnancy

This narrative systematic review evaluates growing evidence of an association between low maternal vitamin D status and increased risk of hypertensive disorders. The inclusion of interventional, observational, and dietary studies on vitamin D and all hypertensive disorders of pregnancy is a novel aspect of this review, providing a unique contribution to an intensively-researched area that still lacks a definitive conclusion. To date, trial evidence supports a protective effect of combined vitamin D and calcium supplementation against preeclampsia. Conflicting data for an association of vitamin D with gestational hypertensive disorders in observational studies arises from a number of sources, including large heterogeneity between study designs, lack of adherence to standardized perinatal outcome definitions, variable quality of analytical data for 25-hydroxyvitamin D (25(OH)D), and inconsistent data reporting of vitamin D status. While evidence does appear to lean towards an increased risk of gestational hypertensive disorders at 25(OH)D concentrations <50 nmol/L, caution should be exercised with dosing in trials, given the lack of data on long-term safety. The possibility that a fairly narrow target range for circulating 25(OH)D for achievement of clinically-relevant improvements requires further exploration. As hypertension alone, and not preeclampsia specifically, limits intrauterine growth, evaluation of the relationship between vitamin D status and all terms of hypertension in pregnancy is a clinically relevant area for research and should be prioritised in future randomised trials.

The profiles of soluble adhesion molecules in the "great obstetrical syndromes". J Matern Fetal Neonatal Med 2018;32:2113-2136. [PMID: 29320948 DOI: 10.1080/14767058.2018.1427058]

OBJECTIVE

The objective of this study was to determine the profiles of maternal plasma soluble adhesion molecules in patients with preeclampsia, small-for-gestational-age (SGA) fetuses, acute pyelonephritis, preterm labor with intact membranes (PTL), preterm prelabor rupture of the membranes (preterm PROM), and fetal death.

MATERIALS AND METHODS

A cross-sectional study was conducted to determine maternal plasma concentrations of sE-selectin, sL-selectin, and sP-selectin as well as sICAM-1, sVCAM-1, and sPECAM-1 in patients with (1) an uncomplicated pregnancy (control, n = 100); (2) preeclampsia (n = 94); (3) SGA fetuses (in women without preeclampsia/hypertension, n = 45); (4) acute pyelonephritis (n = 25); (5) PTL (n = 53); (6) preterm PROM (n = 24); and (7) fetal death (n = 34). Concentrations of soluble adhesion molecules and inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-8) were determined with sensitive and specific enzyme-linked immunoassays.

RESULTS

In comparison to women with a normal pregnancy, (1) women with preeclampsia had higher median concentrations of sE-selectin, sP-selectin, and sVCAM-1, and a lower concentration of sL-selectin (all p values < .001); (2) patients with SGA fetuses had higher median concentrations of sE-selectin, sP-selectin, and sVCAM-1 (all p values < .05); (3) patients with a fetal death had higher median concentrations of sE-selectin and sP-selectin (all p values < .05); (4) patients with acute pyelonephritis had higher median plasma concentrations of sE-selectin, sICAM-1, and sVCAM-1 (all p values < .001); (5) patients with preeclampsia and acute pyelonephritis, plasma concentrations of sVCAM-1, sE-selectin, and sP-selectin correlated with those of the proinflammatory cytokines TNF-α and interleukin (IL)-8 (all p values < .05); (6) patients with PTL had a higher median concentration of sP-selectin and a lower median concentration of VCAM-1 (all p values < .05); and (7) women with preterm PROM had lower median concentrations of sL-selectin and sVCAM-1 (all p values < .05).

CONCLUSIONS

The results of this study show that endothelial cell activation/dysfunction reflected by the plasma concentration of sE-selectin is not specific to preeclampsia but is present in pregnancies complicated by SGA fetuses, acute pyelonephritis, and fetal death. Collectively, we report that each obstetrical syndrome appears to have a stereotypical profile of soluble adhesion molecules in the peripheral circulation.

The role of vitamin D in pre-eclampsia: a systematic review

BACKGROUND

The etiology of pre-eclampsia (PE) is not yet fully understood, though current literature indicates an upregulation of inflammatory mediators produced by the placenta as a potential causal mechanism. Vitamin D is known to have anti-inflammatory properties and there is evidence of an inverse relationship between dietary calcium intake and the incidence of PE. Evidence of the role of vitamin D status and supplementation in the etiology and prevention of PE is reviewed in this article along with identification of research gaps to inform future studies.

METHODS

We conducted a structured literature search using MEDLINE electronic databases to identify published studies until February 2015. These sources were retrieved, collected, indexed, and assessed for availability of pregnancy-related data on PE and vitamin D.

RESULTS

Several case-control studies and cross-sectional studies have shown an association between vitamin D status and PE, although evidence has been inconsistent. Clinical trials to date have been unable to show an independent effect of vitamin D supplementation in preventing PE.

CONCLUSIONS

The included clinical trials do not show an independent effect of vitamin D supplementation in preventing PE; however, issues with dose, timing, and duration of supplementation have not been completely addressed.

Failure of physiologic transformation of spiral arteries, endothelial and trophoblast cell activation, and acute atherosis in the basal plate of the placenta

BACKGROUND

Failure of physiologic transformation of spiral arteries has been reported in preeclampsia, fetal growth restriction, fetal death, and spontaneous preterm labor with intact or ruptured membranes. Spiral arteries with failure of physiologic transformation are prone to develop atherosclerotic-like lesions of atherosis. There are striking parallels between preeclampsia and atherosclerotic disease, and between lesions of atherosis and atherosclerosis. Endothelial activation, identified by intercellular adhesion molecule-1 expression, is present in atherosclerotic-like lesions of heart transplantation, and is considered a manifestation of rejection. Similarly, endothelial activation/dysfunction has been implicated in the pathophysiology of atherosclerosis and preeclampsia. Intercellular adhesion molecule-1-overexpressing-activated endothelial cells are more resistant to trophoblast displacement than nonactivated endothelium, and may contribute to shallow spiral artery trophoblastic invasion in obstetrical syndromes having failure of physiologic transformation.

OBJECTIVE

We sought to determine whether failure of spiral artery physiologic transformation was associated with activation of interstitial extravillous trophoblasts and/or spiral artery endothelium and presence of acute atherosis in the placental basal plate.

STUDY DESIGN

A cross-sectional study of 123 placentas (19-42 weeks' gestation) obtained from normal pregnancies (n = 22), preterm prelabor rupture of membranes (n = 26), preterm labor (n = 23), preeclampsia (n = 27), intrauterine fetal death (n = 15), and small for gestational age (n = 10) was performed. Failure of spiral artery physiologic transformation and presence of cell activation was determined using immunohistochemistry of placental basal plates containing a median of 4 (minimum: 1; maximum: 9) vessels per placenta. Endothelial/trophoblast cell activation was defined by the expression of intercellular adhesion molecule-1. Investigators examining microscopic sections were blinded to clinical diagnosis. Pairwise comparisons among placenta groups were performed with Fisher exact test and Wilcoxon rank sum test using a Bonferroni-adjusted level of significance (.025).

RESULTS

We found that 87% (94/108) of placentas having spiral arteries with failure of physiologic transformation (actin-positive and cytokeratin-negative) in the basal plate, and 0% (0/15) of placentas having only spiral arteries with complete physiologic transformation (cytokeratin-positive and actin-negative), had arterial endothelial and/or interstitial extravillous trophoblasts reactive with the intercellular adhesion molecule-1 activation marker (P < .001). A significant correlation (R² = 0.84) was found between expression of spiral artery endothelial and interstitial extravillous trophoblast intercellular adhesion molecule-1 (P < .001) in activated placentas. Lesions of atherosis were found in 31.9% (30/94) of placentas with complete and/or partial failure of physiologic transformation of spiral arteries that were intercellular adhesion molecule-1-positive, in none of the 14 placentas with failure of physiologic transformation that were intercellular adhesion molecule-1-negative, and in none of the 15 placentas with complete spiral artery physiologic transformation without failure (P = .001). All placentas (30/30, 100%) with atherosis were identified in placentas having concomitant spiral artery endothelial and interstitial extravillous trophoblast activation.

CONCLUSION

Failure of spiral artery physiologic transformation in the placental basal plate is associated with interstitial extravillous trophoblast and arterial endothelial activation along with increased frequency of spiral artery atherosis. These findings may be used to improve the characterization of different disorders of the placental bed such as in refining the existing tools for the early prediction of risk for preterm, preeclamptic, and other abnormal pregnancies.

Daily Cholecalciferol Supplementation during Pregnancy Alters Markers of Regulatory Immunity, Inflammation, and Clinical Outcomes in a Randomized Controlled Trial

BACKGROUND

Vitamin D deficiency is widespread in pregnancy and has been associated with adverse health conditions in mothers and infants. Vitamin D supplementation in pregnancy may support the maintenance of pregnancy by its effects on innate and adaptive immunity.

OBJECTIVE

We assessed the effects of vitamin D supplementation during pregnancy on vitamin D status and markers of immune function associated with adverse pregnancy outcomes.

METHODS

We conducted a randomized, controlled, double-blind intervention of 2 doses of cholecalciferol (400 and 2000 IU/d) from <20 wk to delivery in 57 pregnant women. Vitamin D status, regulatory and inflammatory T cells, markers of innate immunity and systemic inflammation, and clinical outcomes including maternal blood pressure and birth weight were assessed at 26 and 36 wk of pregnancy.

RESULTS

Supplementation with 2000 IU/d vitamin D had a greater effect on the change in vitamin D status over pregnancy (P < 0.0001) and the final value at 36 wk (P < 0.0001) than 400 IU/d, increasing serum 25-hydroxyvitamin D from 81.1 nmol/L at baseline to 116 nmol/L at 36 wk and from 69.6 nmol/L at baseline to 85.6 nmol/L at 36 wk, respectively. The 2000-IU/d group had 36% more interleukin-10⁺ regulatory CD4⁺ T cells at 36 wk than did the 400-IU/d group (P < 0.007). The daily intake of 2000 compared with 400 IU/d tended to dampen the pregnancy-related increase in diastolic blood pressure by 1.3-fold (P = 0.06) and increase birth weight by 8.6% (P = 0.06), but these differences were not statistically significant.

CONCLUSIONS

Supplementation with 2000 IU/d is more effective at increasing vitamin D status in pregnant women than 400 IU/d and is associated with increased regulatory T cell immunity that may prevent adverse outcomes caused by excess inflammation. This trial was registered at clinicaltrials.gov as NCT01417351.

Low maternal 25-hydroxyvitamin D concentration increases the risk of severe and mild preeclampsia

PURPOSE

The objective of this case-cohort study was to evaluate the relationship between maternal 25-hydroxyvitamin D (25(OH)D) concentration and preeclampsia overall and by severity.

METHODS

From an eligible cohort of 12,861 women who had serum banked from aneuploidy screening in Pittsburgh, Pennsylvania from 1999 to 2010, we randomly sampled a subcohort of 2327 pregnancies and all remaining preeclampsia cases (n = 650 cases). Preeclampsia (defined as new-onset hypertension and proteinuria) and its mild and severe forms were identified using ICD-9 codes. Maternal serum collected at 20 weeks or less gestation was measured for 25(OH)D. We used log-binomial regression with restricted cubic splines to estimate the association between 25(OH)D and preeclampsia after adjusting for confounders.

RESULTS

Approximately 21% of the randomly selected sample had 25(OH)D less than 50 nmol per L. We found that the adjusted risk of preeclampsia declined as serum 25(OH)D increased to 50 nmol per L and then plateaued (test of nonlinearity P < .05). The adjusted preeclampsia risk ratios (95% confidence intervals) for 25(OH)D less than 25 nmol per L, 25 to 49.9 nmol per L, and 50 to 74.9 nmol per L were 2.4 (1.2-4.8), 1.1 (0.69-1.7), and 1.3 (0.89-1.8), respectively, compared with those with 25(OH)D 75 nmol per L and over. Similar associations were observed with severe and mild preeclampsia.

CONCLUSIONS

Vitamin D deficiency increases risks of severe and mild forms of preeclampsia.

Seasonality of gestational diabetes mellitus: a South Australian population study

OBJECTIVE

To investigate whether there is a seasonal variation in the incidence of gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

This retrospective cohort study of 60 306 eligible South Australian live-born singletons during 2007-2011 recorded in the South Australian Perinatal Statistics Collection (SAPSC) examined the incidence of GDM in relation to estimated date of conception (eDoC). Fourier series analysis was used to model seasonal trends.

RESULTS

During the study period, 3632 (6.0%) women were diagnosed with GDM. Seasonal modeling showed a strong relation between GDM and eDoC (p<0.001). Unadjusted and adjusted models (adjusted for maternal age, body mass index (BMI), parity, ethnicity, socioeconomic status, and chronic hypertension) demonstrated the presence of a peak incidence occurring among pregnancies with eDoC in winter (June/July/August), with a trough for eDoc in summer (December/January/February). As this was a retrospective study, we could only use variables that had been collected as part of the routine registration system, the SAPSC.

CONCLUSIONS

This study is the first population-based study to demonstrate a seasonal variation for GDM. Several maternal lifestyle and psychosocial factors associated with seasonality and GDM may be influential in the pathophysiologic mechanisms of GDM. Ambient temperature, physical activity, nutrient intake, and vitamin D levels may affect maternal physiology, and fetal and placental development at the cellular level and contribute to the development of GDM. The mechanisms underlying these possible associations are not fully understood and warrant further investigation.

Early pregnancy vitamin D status and risk for adverse maternal and infant outcomes in a bi-ethnic cohort: the Behaviors Affecting Baby and You (B.A.B.Y.) Study

Vitamin D deficiency is common during pregnancy and higher in Hispanic as compared with non-Hispanic white women. However, the association between vitamin D deficiency and adverse pregnancy outcomes remains unclear and may vary across ethnic groups, in part because of genetic variation in the metabolism of vitamin D. Few studies have included Hispanic women. Therefore, we investigated this association among 237 participants in the Behaviors Affecting Baby and You Study, a randomised trial of an exercise intervention among ethnically diverse prenatal care patients in Massachusetts. Baseline serum 25-hydroxyvitamin D (25(OH)D) was measured at 15·2 (sd 4·7) weeks' gestation. Information on adverse pregnancy outcomes was abstracted from medical records. Mean 25(OH)D was 30·4 (sd 12·0) ng/ml; 53·2 % of participants had insufficient (<30 ng/ml) and 20·7 % had deficient (<20 ng/ml) 25(OH)D levels. After adjusting for month of blood draw, gestational age at blood draw, gestational age at delivery, age, BMI and Hispanic ethnicity, women with insufficient and deficient vitamin D had infants with birth weights 139·74 (se 69·16) g (P=0·045) and 175·52 (se 89·45) g (P=0·051) lower compared with women with sufficient vitamin D levels (≥30 ng/ml). Each 1 ng/ml increase in 25(OH)D was associated with an increased risk for gestational diabetes mellitus among Hispanic women only (relative risk 1·07; 95 % CI 1·03, 1·11) in multivariable analysis. We did not observe statistically significant associations between maternal vitamin D status and other pregnancy outcomes. Our findings provide further support for an adverse impact of vitamin D deficiency on birth weight in Hispanic women.

Is first trimester vitamin D status in nulliparous women associated with pregnancy related hypertensive disorders?

OBJECTIVES

this study aimed to explore if maternal vitamin D status in early pregnancy was associated with pre-eclampsia and pregnancy-induced hypertension. Relationships between vitamin D status and blood pressure at the start of pregnancy as well as the occurrence of a mid-pregnancy drop in blood pressure were also explored. This secondary analysis was completed to investigate a possible mechanism for the association between vitamin D status and pregnancy related hypertensive disorders.

DESIGN AND SETTING

data were obtained from the Amsterdam Born Children and their Development study, a prospective community-based cohort study based in Amsterdam, The Netherlands.

PARTICIPANTS

a total of 2074 nulliparous women without pre-existing hypertension and with a known vitamin D status before 17 weeks gestation were included in the study. Vitamin D status was categorized into four groups: "normal" (≥50nmol/L), "insufficient" (30-49.9nmol/L) "deficient" (20-29.9nmol/L) or "severely deficient" (<20nmol/L).

MEASUREMENTS

logistic regression analysis was used to investigate if vitamin D status was related to the odds of experiencing pre-eclampsia or pregnancy-induced hypertension. Models were corrected for maternal age, ethnicity, pre-pregnancy BMI, smoking and socioeconomic status. χ(2) and ANOVA tests were used to investigate relationships between vitamin D status and the blood pressure parameters.

FINDINGS

when compared to women with a normal vitamin D status, women who were severely deficient had an increased risk for pre-eclampsia (OR 2.08; 95% CI, 1.05-4.13), but the association was rendered non-significant after correction (OR 1.88; 95% CI 0.79-4.48). There were no associations between vitamin D status and pregnancy-induced hypertension, starting blood pressure or the occurrence of a mid-pregnancy drop in blood pressure.

KEY CONCLUSIONS

no strong evidence was found for an association between first trimester vitamin D status and pregnancy related hypertensive disorders in nulliparous women.

IMPLICATIONS FOR PRACTICE

at this time, vitamin D supplementation is not warranted for the specific purpose of preventing pregnancy related hypertensive disorders.

Immunomodulatory role of vitamin D in the pathogenesis of preeclampsia

Worldwide, preeclampsia is a significant health risk to both pregnant women and their unborn children. Despite scientific advances, the exact pathogenesis of preeclampsia is not yet fully understood. Meanwhile, the incidence of preeclampsia is expected to increase. A series of potential etiologies for preeclampsia has been identified, including endothelial dysfunction, immunological dysregulation and trophoblastic invasion. In this literature review, we have critically reviewed existing literature regarding the research findings that link the role of vitamin D to the pathogenesis and immunoregulation of preeclampsia. The relationship of vitamin D with the suspected etiologies of preeclampsia underscores its clinical potential in the diagnosis and treatment of preeclampsia.

Regulation of calcitriol biosynthesis and activity: focus on gestational vitamin D deficiency and adverse pregnancy outcomes

Vitamin D has garnered a great deal of attention in recent years due to a global prevalence of vitamin D deficiency associated with an increased risk of a variety of human diseases. Specifically, hypovitaminosis D in pregnant women is highly common and has important implications for the mother and lifelong health of the child, since it has been linked to maternal and child infections, small-for-gestational age, preterm delivery, preeclampsia, gestational diabetes, as well as imprinting on the infant for life chronic diseases. Therefore, factors that regulate vitamin D metabolism are of main importance, especially during pregnancy. The hormonal form and most active metabolite of vitamin D is calcitriol. This hormone mediates its biological effects through a specific nuclear receptor, which is found in many tissues including the placenta. Calcitriol synthesis and degradation depend on the expression and activity of CYP27B1 and CYP24A1 cytochromes, respectively, for which regulation is tissue specific. Among the factors that modify these cytochromes expression and/or activity are calcitriol itself, parathyroid hormone, fibroblast growth factor 23, cytokines, calcium and phosphate. This review provides a current overview on the regulation of vitamin D metabolism, focusing on vitamin D deficiency during gestation and its impact on pregnancy outcomes.

Maternal vitamin D status and the risk of mild and severe preeclampsia

BACKGROUND

We sought to determine the association between maternal vitamin D status at ≤26 weeks' gestation and the risk of preeclampsia by clinical subtype.

METHODS

We conducted a case-cohort study among women enrolled at 12 US sites from 1959 to 1966 in the Collaborative Perinatal Project. In serum collected at ≤26 weeks' gestation (median 20.9 weeks) from 717 women who later developed preeclampsia (560 mild and 157 severe cases) and from 2986 mothers without preeclampsia, we measured serum 25-hydroxyvitamin D, over 40 years later, using liquid chromatography-tandem mass spectrometry.

RESULTS

Half of women in the subcohort had 25-hydroxyvitamin D (25(OH)D) >50 nmol/L. Maternal 25(OH)D 50 to 74.9 nmol/L was associated with a reduction in the absolute and relative risk of preeclampsia and mild preeclampsia compared with 25(OH)D <30 nmol/L in the crude analysis but not after adjustment for confounders, including race, prepregnancy body mass index, and parity. For severe preeclampsia, 25(OH)D ≥50 nmol/L was associated with a reduction in three cases per 1000 pregnancies (adjusted risk difference = -0.003 [95% confidence interval = -0.005 to 0.0002]) and a 40% reduction in risk (0.65 [0.43 to 0.98]) compared with 25(OH)D <50 nmol/L. Conclusions were unchanged (1) after restricting to women with 25(OH)D measured before 22 weeks' gestation or (2) with formal sensitivity analyses for unmeasured confounding.

CONCLUSIONS

Maternal vitamin D deficiency may be a risk factor for severe preeclampsia but not for its mild subtypes. Contemporary cohorts with large numbers of severe preeclampsia cases would be needed to confirm or refute these findings.

Role of vitamin D in ovarian physiology and its implication in reproduction: a systematic review

OBJECTIVE

To report an update on the role of vitamin D (VD) in ovarian physiology with a focus on genes involved in steroidogenesis, follicular development, and ovarian reserve, as well as ovulatory dysfunction associated with polycystic ovary syndrome (PCOS), and ovarian response to assisted reproductive technology (ART).

DESIGN

Systematic review.

SETTING

Not applicable.

PATIENT(S)

Human, animal, and cell culture models.

INTERVENTION(S)

Pubmed literature search.

MAIN OUTCOME MEASURE(S)

Granulosa cell function, serum antimüllerian hormone (AMH), AMH and its receptor gene expression, soluble receptor for advanced glycation end-products (sRAGE), PCOS parameters, and ART outcome.

RESULT(S)

In human granulosa cells, VD alters AMH signaling, FSH sensitivity, and progesterone production and release, indicating a possible physiologic role for VD in ovarian follicular development and luteinization. In the serum, 25-hydroxyvitamin D (25OH-D) is positively correlated with AMH, and appropriate VD supplementation in VD-depleted women can suppress the seasonal changes that occur in serum AMH. In VD-deficient women with PCOS, VD supplementation lowers the abnormally elevated serum AMH levels, possibly indicating a mechanism by which VD improves folliculogenesis. The antiinflammatory sRAGE serum levels significantly increase in women with PCOS after VD replacement. Although follicular fluid 25OH-D correlates with IVF outcomes, there is a lack of data pertaining to the impact of VD supplementation on pregnancy rates following IVF.

CONCLUSION(S)

This review underscores the need for understanding the mechanistic actions of VD in ovarian physiology and the critical need for randomized trials to elucidate the impact of VD supplementation on controlled ovarian hyperstimulation/IVF outcome and ovulatory dysfunction associated with PCOS.

Maternal vitamin D status and small-for-gestational-age offspring in women at high risk for preeclampsia

OBJECTIVE

To examine the association between second-trimester maternal serum 25-hydroxyvitamin D concentrations and risk of small for gestational age (SGA) in singleton live births.

METHODS

We assayed serum samples at 12-26 weeks of gestation for 25-hydroxyvitamin D in a sample of participants in a multicenter clinical trial of low-dose aspirin for the prevention of preeclampsia in high-risk women (n=792). Multivariable log-binomial regression models were used to assess the association between 25-hydroxyvitamin D and risk of SGA (birth weight less than the 10 percentile for gestational age) after adjustment for confounders including maternal prepregnancy obesity, race, treatment allocation, and risk group.

RESULTS

Thirteen percent of neonates were SGA at birth. Mean (standard deviation) 25-hydroxyvitamin D concentrations were lower in women who delivered SGA (57.9 [29.9] nmol/L) compared with non-SGA neonates (64.8 [29.3] nmol/L, P=.028). In adjusted models, 25-hydroxyvitamin D concentrations of 50-74 nmol/L and 75 nmol/L or greater compared with less than 30 nmol/L were associated with 43% (95% confidence interval [CI] 0.33-0.99) and 54% (95% CI 0.24-0.87) reductions in risk of SGA, respectively. Race and maternal obesity each modified this association. White women with 25-hydroxyvitamin D 50 nmol/L or greater compared with less than 50 nmol/L had a 68% reduction in SGA risk (adjusted risk ratio 0.32, 95% CI 0.17-0.63) and nonobese women with 25-hydroxyvitamin D 50 nmol/L or greater compared with less than 50 nmol/L had a 50% reduction in SGA risk (adjusted risk ratio 0.50, 95% CI 0.31-0.82). There was no association between 25-hydroxyvitamin D and risk of SGA in black or obese mothers.

CONCLUSION

Maternal vitamin D status in the second trimester is associated with risk of SGA among all women and in the subgroups of white and nonobese women.

LEVEL OF EVIDENCE

II.

First trimester maternal serum vitamin D and markers of preeclampsia

OBJECTIVE

There is evidence that vitamin D deficiency is associated with preeclampsia. The aim of the study was to determine if maternal levels of vitamin D at 1st trimester were related to markers of preeclampsia.

MATERIAL

Serum levels of 25-hydroxy-vitamin D (25OHD), PAPP-A, PlGF, uterine artery pulsatility index and mean arterial pressure were measured in 280 pregnant women.

RESULTS

Preeclampsia markers were not related to 25OHD concentration.

CONCLUSION

First trimester maternal serum concentration of vitamin D does not seem to be connected with markers of preeclampsia.