Different pathways for preterm birth between singleton and twin pregnancies: a population-based registry study of 481 176 nulliparous women.

OBJECTIVE: To explore the contribution of pregnancy-related complications on the prevalence of extremely, very and late preterm births in singleton and twin pregnancies. To study the risk of spontaneous preterm birth in twin pregnancies compared with singleton pregnancies. DESIGN: Population-based registry study. SETTING: Medical birth registry of Norway and Statistics Norway. POPULATION: Nulliparous women with singleton (n = 472 449) or twin (n = 8727) births during 1999-2018. METHODS: Prevalence rates of pregnancy-related complications for extremely, very and late preterm birth in twin and singleton pregnancies were calculated with 95% confidence intervals. Multivariable logistic regression was applied to assess odds ratios for preterm birth, adjusted for obstetric and socio-economic factors. MAIN OUTCOME MEASURES: Extremely preterm (<28+0  weeks of gestation), very preterm (28+0 -33+6  weeks of gestation) and late preterm (34+0 -36+6  weeks of geatation) birth. RESULTS: Preterm birth was significantly more prevalent in twin pregnancies than in singleton pregnancies in all categories: all preterm (54.7% vs 6.1%), extremely preterm (3.6% vs 0.4%), very preterm (18.2% vs 1.4%) and late preterm (33.0% vs 4.3%) births. Stillbirth, congenital malformation and pre-eclampsia were more prevalent in twin pregnancies than in singleton pregnancies, but the prevalence of complications differed in the three categories of preterm birth. Pre-eclampsia was more prevalent in singleton than in twin pregnancies ending in extremely and very preterm birth. The adjusted odds of spontaneous preterm live birth were between 19- and 54-fold greater in twin pregnancies than in singleton pregnancies. CONCLUSIONS: Singleton and twin pregnancies seem to have different pathways leading to extremely, very and late preterm birth.

Markers of placental function correlate with prevalence and quantity of nucleated fetal cells in maternal circulation in normotensive term pregnancies.

INTRODUCTION: Transplacental fetal cell transfer results in the engraftment of fetal-origin cells in the pregnant woman's body, a phenomenon termed fetal microchimerism. Increased fetal microchimerism measured decades postpartum is implicated in maternal inflammatory disease. Understanding which factors cause increased fetal microchimerism is therefore important. During pregnancy, circulating fetal microchimerism and placental dysfunction increase with increasing gestational age, particularly towards term. Placental dysfunction is reflected by changes in circulating placenta-associated markers, specifically placental growth factor (PlGF), decreased by several 100 pg/mL, soluble fms-like tyrosine kinase-1 (sFlt-1), increased by several 1000 pg/mL, and the sFlt-1/PlGF ratio, increased by several 10 (pg/mL)/(pg/mL). We investigated whether such alterations in placenta-associated markers correlate with an increase in circulating fetal-origin cells. MATERIAL AND METHODS: We included 118 normotensive, clinically uncomplicated pregnancies (gestational age 37+1 up to 42+2 weeks' gestation) pre-delivery. PlGF and sFlt-1 (pg/mL) were measured by Elecsys® Immunoassays. We extracted DNA from maternal and fetal samples and genotyped four human leukocyte antigen loci and 17 other autosomal loci. Paternally inherited, unique fetal alleles served as polymerase chain reaction (PCR) targets for detecting fetal-origin cells in maternal buffy coat. Fetal-origin cell prevalence was assessed by logistic regression, and quantity by negative binomial regression. Statistical exposures included gestational age (weeks), PlGF (100 pg/mL), sFlt-1 (1000 pg/mL) and the sFlt-1/PlGF ratio (10 (pg/mL)/(pg/mL)). Regression models were adjusted for clinical confounders and PCR-related competing exposures. RESULTS: Gestational age was positively correlated with fetal-origin cell quantity (DRR = 2.2, P = 0.003) and PlGF was negatively correlated with fetal-origin cell prevalence (odds ratio [OR]100 = 0.6, P = 0.003) and quantity (DRR100 = 0.7, P = 0.001). The sFlt-1 and the sFlt-1/PlGF ratios were positively correlated with fetal-origin cell prevalence (OR1000 = 1.3, P = 0.014 and OR10 = 1.2, P = 0.038, respectively), but not quantity (DRR1000 = 1.1, P = 0.600; DRR10 = 1.1, P = 0.112, respectively). CONCLUSIONS: Our results suggest that placental dysfunction as evidenced by placenta-associated marker changes, may increase fetal cell transfer. The magnitudes of change tested were based on ranges in PlGF, sFlt-1 and the sFlt-1/PlGF ratio previously demonstrated in pregnancies near and post-term, lending clinical significance to our findings. Our results were statistically significant after adjusting for confounders including gestational age, supporting our novel hypothesis that underlying placental dysfunction potentially is a driver of increased fetal microchimerism.

Failure of physiological transformation and spiral artery atherosis: their roles in preeclampsia.

Physiological transformation with remodeling of the uteroplacental spiral arteries is key to a successful placentation and normal placental function. It is an intricate process that involves, but is not restricted to, complex interactions between maternal decidual immune cells and invasive trophoblasts in the uterine wall. In normal pregnancy, the smooth muscle cells of the arterial tunica media of uteroplacental spiral arteries are replaced by invading trophoblasts and fibrinoid, and the arterial diameter increases 5- to 10-fold. Poor remodeling of the uteroplacental spiral arteries is linked to early-onset preeclampsia and several other major obstetrical syndromes, including fetal growth restriction, placental abruption, and spontaneous preterm premature rupture of membranes. Extravillous endoglandular and endovenous trophoblast invasions have recently been put forth as potential contributors to these syndromes as well. The well-acknowledged disturbed extravillous invasion of maternal spiral arteries in preeclampsia is summarized, as are briefly novel concepts of disturbed extravillous endoglandular and endovenous trophoblast invasions. Acute atherosis is a foam cell lesion of the uteroplacental spiral arteries associated with poor remodeling. It shares some morphologic features with early stages of atherosclerosis, but several molecular differences between these lesions have also recently been revealed. Acute atherosis is most prevalent at the maternal-fetal interface, at the tip of the spiral arteries. The localization of acute atherosis downstream of poorly remodeled arteries suggests that alterations in blood flow may trigger inflammation and foam cell development. Acute atherosis within the decidua basalis is not, however, confined to unremodeled areas of spiral arteries or to hypertensive disorders of pregnancy and may even be present in some clinically uneventful pregnancies. Given that foam cells of atherosclerotic lesions are known to arise from smooth muscle cells or macrophages activated by multiple types of inflammatory stimulation, we have proposed that multiple forms of decidual vascular inflammation may cause acute atherosis, with or without poor remodeling and/or preeclampsia. Furthermore, we propose that acute atherosis may develop at different gestational ages, depending on the type and degree of the inflammatory insult. This review summarizes the current knowledge of spiral artery remodeling defects and acute atherosis in preeclampsia. Some controversies will be presented, including endovascular and interstitial trophoblast invasion depths, the concept of 2-stage trophoblast invasion, and whether the replacement of maternal spiral artery endothelium by fetal endovascular trophoblasts is permanent. We will discuss the role of acute atherosis in the pathophysiology of preeclampsia and short- and long-term health correlates. Finally, we suggest future opportunities for research on this intriguing uteroplacental interface between the mother and fetus.

Placental Transcriptome Profiling in Subtypes of Diabetic Pregnancies Is Strongly Confounded by Fetal Sex.

The placenta is a temporary organ with a unique structure and function to ensure healthy fetal development. Placental dysfunction is involved in pre-eclampsia (PE), fetal growth restriction, preterm birth, and gestational diabetes mellitus (GDM). A diabetic state affects maternal and fetal health and may lead to functional alterations of placental metabolism, inflammation, hypoxia, and weight, amplifying the fetal stress. The placental molecular adaptations to the diabetic environment and the adaptive spatio-temporal consequences to elevated glucose or insulin are largely unknown (2). We aimed to identify gene expression signatures related to the diabetic placental pathology of placentas from women with diabetes mellitus. Human placenta samples (n = 77) consisting of healthy controls, women with either gestational diabetes mellitus (GDM), type 1 or type 2 diabetes, and women with GDM, type 1 or type 2 diabetes and superimposed PE were collected. Interestingly, gene expression differences quantified by total RNA sequencing were mainly driven by fetal sex rather than clinical diagnosis. Association of the principal components with a full set of clinical patient data identified fetal sex as the single main explanatory variable. Accordingly, placentas complicated by type 1 and type 2 diabetes showed only few differentially expressed genes, while possible effects of GDM and diabetic pregnancy complicated by PE were not identifiable in this cohort. We conclude that fetal sex has a prominent effect on the placental transcriptome, dominating and confounding gene expression signatures resulting from diabetes mellitus in settings of well-controlled diabetic disease. Our results support the notion of placenta as a sexual dimorphic organ.

The association between placenta-associated circulating biomarkers and composite adverse delivery outcome of a likely placental cause in healthy post-date pregnancies.

INTRODUCTION: Post-date pregnancies have an increased risk of adverse delivery outcome. Our aim was to explore the association between placenta-associated circulating biomarkers and composite adverse delivery outcome of a likely placental cause in clinically healthy post-date pregnancies. MATERIAL AND METHODS: Women with healthy singleton post-date pregnancies between 40+2 and 42+2  weeks of gestation were recruited to this prospective, observational study conducted at Oslo University Hospital, Norway (NCT03100084). Placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) were measured in the maternal serum samples closest to delivery. The composite adverse delivery outcome included fetal acidemia, low Apgar score (<4 at 1 min or <7 at 5 min), asphyxia, fetal death, assisted ventilation for more than 6 h, meconium aspiration, hypoxic-ischemic encephalopathy, therapeutic hypothermia, operative delivery due to fetal distress, or pathological placental histology findings. Two study-independent senior consultant obstetricians blinded to biomarker results concluded, based on clinical expert opinion, whether the adverse delivery outcomes were most likely associated with placental dysfunction ("likely placental cause") or not. Means were compared using one-way analysis of variance and Bonferroni corrected pairwise comparisons between groups. Receiver operating characteristic (ROC) curves assessed the predictive ability of PlGF, sFlt-1/PlGF ratio, and PlGF <10th centile after adjustment for gestational age at blood sampling. RESULTS: Of 501 pregnancies reviewed for predefined adverse delivery outcomes and for a likely placental cause, 468 were healthy pregnancies and subsequently assigned to either the "uncomplicated" (no adverse outcome, n = 359), "intermediate" (non-placental cause/undetermined, n = 90), or "complicated" (likely placental cause, n = 19) group. There was a significant difference in mean PlGF and sFlt-1/PlGF ratio between the "complicated", "intermediate", and "uncomplicated" groups (108, 185, and 179 pg/mL, p = 0.001; and 48.3, 23.4, and 24.6, p = 0.002, respectively). There was a higher proportion of PlGF concentration <10th centile in the "complicated" group compared with the "intermediate" and "uncomplicated" groups (42.1% vs. 11.1% and 9.5%, p = 0.001). The largest area under the ROC curve for predicting "complicated" outcome was achieved by PlGF concentration and gestational age at blood sampling (0.76; 95% CI 0.65-0.86). CONCLUSIONS: In clinically healthy post-date pregnancies, an antiangiogenic pre-delivery profile (lower PlGF level and higher sFlt-1/PlGF ratio) was associated with composite adverse delivery outcome of a likely placental cause.

Kidney Injury Caused by Preeclamptic Pregnancy Recovers Postpartum in a Transgenic Rat Model.

Preeclampsia (PE) is characterized by the onset of hypertension (≥140/90 mmHg) and presence of proteinuria (>300 mg/L/24 h urine) or other maternal organ dysfunctions. During human PE, renal injuries have been observed. Some studies suggest that women with PE diagnosis have an increased risk to develop renal diseases later in life. However, in human studies PE as a single cause of this development cannot be investigated. Here, we aimed to investigate the effect of PE on postpartum renal damage in an established transgenic PE rat model. Female rats harboring the human-angiotensinogen gene develop a preeclamptic phenotype after mating with male rats harboring the human-renin gene, but are normotensive before and after pregnancy. During pregnancy PE rats developed mild tubular and glomerular changes assessed by histologic analysis, increased gene expression of renal damage markers such as kidney injury marker 1 and connective-tissue growth factor, and albuminuria compared to female wild-type rats (WT). However, four weeks postpartum, most PE-related renal pathologies were absent, including albuminuria and elevated biomarker expression. Only mild enlargement of the glomerular tuft could be detected. Overall, the glomerular and tubular function were affected during pregnancy in the transgenic PE rat. However, almost all these pathologies observed during PE recovered postpartum.

Gestational age reference ranges for umbilical cord blood lactate: An external validation study of post-date pregnancies.

A previous study published in 2008 by Wiberg et al demonstrated increasing umbilical cord blood lactate at delivery by gestational age in vigorous offspring (n = 10 169, gestational age 24-43 weeks). Based on these results the authors concluded that gestational age-independent umbilical cord lactate cut-off could give false-negative or false-positive diagnosis of lacticemia. To our knowledge, these findings have not been incorporated into clinical interpretations in delivery units. To perform an external validity study for the findings by Wiberg et al, we analyzed umbilical cord blood lactate levels according to gestational age in a post-date delivery study population at our large, tertiary obstetric unit. The parallel finding of our study to that of Wiberg et al highlights the importance of using available gestational age dependent reference ranges (eg as presented in Wiberg's publication), when interpreting umbilical cord blood lactate levels for fetal wellbeing.

Placental Senescence and the Two-Stage Model of Preeclampsia.

In this review, we summarize how an increasingly stressed and aging placenta contributes to the maternal clinical signs of preeclampsia, a potentially lethal pregnancy complication. The pathophysiology of preeclampsia has been conceptualized in the two-stage model. Originally, highlighting the importance of poor placentation for early-onset preeclampsia, the revised two-stage model explains late-onset preeclampsia as well, which is often preceded by normal placentation. We discuss how cellular senescence in the placenta may fit with the framework of the revised two-stage model of preeclampsia pathophysiology and summarize potential cellular and molecular mechanisms, including effects on placental and maternal endothelial function. Cellular senescence may occur in response to inflammatory processes and oxidative, mitochondrial, or endoplasmic reticulum stress and chronic stress induce accelerated, premature placental senescence. In preeclampsia, both circulating and tissue-based senescence markers are present. We suggest that aspirin prophylaxis, commonly recommended from the first trimester onward for women at risk of preeclampsia, may affect placentation and possibly mechanisms of placental senescence, thus attenuating the risk of preeclampsia developing clinically. We propose that biomarkers of placental dysfunction and senescence may contribute to altered preventive strategies, including discontinuation of aspirin at week 24-28 depending on placenta-associated biomarker risk stratification.

Retinal oximetry and microvascular assessment after hypertensive pregnancy complications.

PURPOSE: Women with hypertensive disorders of pregnancy (HDP) are at increased risk of developing premature cardiovascular disease (CVD). The mechanisms behind this are not fully understood, but microvascular alterations have been documented in retinal arterioles and venules. The aim of this study was to use non-invasive retinal imaging to investigate the structural and functional properties of arterioles, venules and capillaries in this patient group. METHODS: We examined 27 women with previous HDP and 23 controls at 3 years postpartum. The retinal microvasculature was assessed by vessel calibre measurements, retinal oximetry and optical coherence tomography angiography. Differences were analysed using non-parametric tests and multiple regression analyses, adjusted for age and body mass index. RESULTS: Median arteriolar oxygen saturation (SaO2; 94.2% vs. 93.0%), venular oxygen saturation (SvO2; 60.1% vs. 62.4%) and arteriovenous saturation difference (AV-difference; 32.8% vs. 32.3%) were similar across groups. Capillary vessel density (VD; 46.2% vs. 46.3%), skeletonised VD (VSD; 21.3 vs. 21.1 mm/mm2) and vessel diameter index (21.65 vs. 21.86) were also comparable. In the HDP group, mean arterial pressure (MAP) was positively correlated with AV-difference (R2 = 0.209) and negatively correlated with arteriolar diameter (CRAE; r2 = 0.382). CONCLUSIONS: Structural microvascular alterations appear not to be key biomarkers for CVD risk after HDP as early as 3 years postpartum in otherwise healthy women. Further studies are needed to evaluate whether such changes occur later in life. MAP was associated with AV-difference only in the HDP group, suggesting specific mechanisms affecting functional microvascular properties in these women.

Hypertensive disorders of pregnancy and long-term maternal cardiovascular risk: Bridging epidemiological knowledge into personalized postpartum care and follow-up.

Cardiovascular disease (CVD) is globally the leading cause of death and disability. Sex-specific causes of female CVD are under-investigated. Pregnancy remains an underinvestigated sex-specific stress test for future CVD and a hitherto missed opportunity to initiate prevention of CVD at a young age. Population-based studies show a strong association between female CVD and hypertensive disorders of pregnancy. This association is also present after other pregnancy complications that are associated with placental dysfunction, including fetal growth restriction, preterm delivery and gestational diabetes mellitus. Few women are, however, offered systematic cardio-preventive follow-up after such pregnancy complications. These women typically seek help from the health system at first clinical symptom of CVD, which may be decades later. By this time, morbidity is established and years of preventive opportunities have been missed out. Early identification of modifiable risk factors starting postpartum followed by systematic preventive measures could improve maternal cardiovascular health trajectories, promoting healthier societies. In this non-systematic review we briefly summarize the epidemiological associations and pathophysiological hypotheses for the associations. We summarize current clinical follow-up strategies, including some proposed by international and national guidelines as well as user support groups. We address modifiable factors that may be underexploited in the postpartum period, including breastfeeding and blood pressure management. We suggest a way forward and discuss the remaining knowledge gaps and barriers for securing the best evidence-based follow-up, relative to available resources after a hypertensive pregnancy complication in order to prevent or delay onset of premature CVD.

Fetal-origin cells in maternal circulation correlate with placental dysfunction, fetal sex, and severe hypertension during pregnancy.

Fetal microchimerism (FMc) arises when fetal cells enter maternal circulation, potentially persisting for decades. Increased FMc is associated with fetal growth restriction, preeclampsia, and anti-angiogenic shift in placenta-associated proteins in diabetic and normotensive term pregnancies. The two-stage model of preeclampsia postulates that placental dysfunction causes such shift in placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFLt-1), triggering maternal vascular inflammation and endothelial dysfunction. We investigated whether anti-angiogenic shift, fetal sex, fetal growth restriction, and severe maternal hypertension correlate with FMc in hypertensive disorders of pregnancy with new-onset features (n = 125). Maternal blood was drawn pre-delivery at > 25 weeks' gestation. FMc was detected by quantitative polymerase chain reaction targeting paternally inherited unique fetal alleles. PlGF and sFlt-1 were measured by immunoassay. We estimated odds ratios (ORs) by logistic regression and detection rate ratios (DRRs) by negative binomial regression. PlGF correlated negatively with FMc quantity (DRR = 0.2, p = 0.005) and female fetal sex correlated positively with FMc prevalence (OR = 5.0, p < 0.001) and quantity (DRR = 4.5, p < 0.001). Fetal growth restriction no longer correlated with increased FMc quantity after adjustment for correlates of placental dysfunction (DRR = 1.5, p = 0.272), whereas severe hypertension remained correlated with both FMc measures (OR = 5.5, p = 0.006; DRR = 6.3, p = 0.001). Our findings suggest that increased FMc is independently associated with both stages of the two-stage preeclampsia model. The association with female fetal sex has implications for microchimerism detection methodology. Future studies should target both male and female-origin FMc and focus on clarifying which placental mechanisms impact fetal cell transfer and how FMc impacts the maternal vasculature.

Placental human papillomavirus infections and adverse pregnancy outcomes.

INTRODUCTION: Knowledge on prevalence and association of human papillomavirus (HPV) in third trimester placentae and adverse pregnancy outcomes is limited. We investigated the prevalence of placental HPV at delivery, explored urine HPV characteristics associated with placental HPV and whether placental HPV increased the risk adverse pregnancy outcomes. METHODS: Pregnant women were enrolled in the Scandinavian PreventADALL mother-child cohort study at midgestation. Human papillomavirus genotyping was performed on placental biopsies collected at delivery (n = 587) and first-void urine at midgestation and delivery (n = 556). Maternal characteristics were collected by questionnaires at gestational week 18 and 34. Adverse pregnancy outcomes were registered from chart data including hypertensive disorders of pregnancy, gestational diabetes mellitus and newborns small for gestational age. Uni- and multivariable regression models were used to investigate associations. RESULTS: Placental HPV was detected in 18/587 (3 %). Twenty-eight genotypes were identified among the 214/556 (38 %) with midgestational urine HPV. Seventeen of the 18 women with placental HPV were midgestational HPV positive with 89 % genotype concordance. Midgestational high-risk-(HR)-HPV and high viral loads of Any- or HR-HPV were associated with placental HPV. Persisting HPV infection from midgestation to delivery was not associated with placental HPV. Adverse pregnancy outcomes were seen in 2/556 (0.4 %) of women with placental HPV. DISCUSSION: In this general cohort of pregnant women, the prevalence of placental HPV was 3 %, and midgestational urinary HPV 38 %. High HPV viral load increased the risk for placental HPV infections. We observed no increased risk for adverse pregnancy outcomes in women with placental HPV.

Cytochrome P450 subfamily 2J polypeptide 2 expression and circulating epoxyeicosatrienoic metabolites in preeclampsia.

BACKGROUND: Preeclampsia is a multisystem disorder of pregnancy, originating in the placenta. Cytochrome P450 (CYP)-dependent eicosanoids regulate vascular function, inflammation, and angiogenesis, which are mechanistically important in preeclampsia. METHODS AND RESULTS: We performed microarray screening of placenta and decidua (maternal placenta) from 25 preeclamptic women and 23 control subjects. The CYP subfamily 2J polypeptide 2 (CYP2J2) was upregulated in preeclamptic placenta and decidua. Reverse-transcription polymerase chain reaction confirmed the upregulation, and immunohistochemistry localized CYP2J2 in trophoblastic villi and deciduas at 12 weeks and term. The CYP2J2 metabolites, 5,6-epoxyeicosatrienoic acid (EET), 14,15-EET, and the corresponding dihydroxyeicosatrienoic acids, were elevated in preeclamptic women compared with controls in the latter two thirds of pregnancy and after delivery. Stimulating a trophoblast-derived cell line with the preeclampsia-associated cytokine tumor necrosis factor-α enhanced CYP2J2 gene and protein expression. In 2 independent rat models of preeclampsia, reduced uterine-perfusion rat and the transgenic angiotensin II rat, we observed elevated EET, dihydroxyeicosatrienoic acid, and preeclamptic features that were ameliorated by the CYP epoxygenase inhibitor N-(methylsulfonyl)-2-(2-propynyloxy)-benzenehexanamide (MsPPOH). Uterine arterial rings of these rats also dilated in response to MsPPOH. Furthermore, 5,6-EET could be metabolized to a thromboxane analog. In a bioassay, 5,6-EET increased the beating rate of neonatal cardiomyocytes. Blocking thromboxane synthesis reversed that finding and also normalized large-conductance calcium-activated potassium channel activity. CONCLUSIONS: Our data implicate CYP2J2 in the pathogenesis of preeclampsia and as a potential candidate for the disturbed uteroplacental remodeling, leading to hypertension and endothelial dysfunction.

Gestational diabetes mellitus, follow-up of future maternal risk of cardiovascular disease and the use of eHealth technologies-a scoping review.

BACKGROUND: Globally, gestational diabetes mellitus complicates 1 in 6 pregnancies and increases future risk of type 2 diabetes and cardiovascular disease in the affected women. There is a lack of consensus on the optimal follow-up of these women. eHealth is emerging as a health care tool, but its practical utility and advantages over standard care in the follow-up after pregnancy complications remains to be determined. Our aim was to systematically review the existing literature on cardiovascular follow-up after gestational diabetes, the utility of eHealth technology for this purpose, and to identify research gaps. METHODS: We performed a systematic scoping review following a published protocol and the Joanna Briggs methodology for studies up until May 2022. Four databases were searched: Ovid MEDLINE, Embase, Maternity and Infant Care, and Cochrane Database of Systematic Reviews. Primary research articles and systematic reviews were included in the final analyses. Two reviewers independently screened abstracts and performed full text assessment. Data was extracted using a data charting form. In all stages of the process, if consensus was not reached, a third reviewer was consulted. The findings from the data charting process provided the basis for summarizing the findings from the included studies. RESULTS: The search of the databases generated 2772 hits. After removing duplicates and manually adding a total of 19 studies, reviews, and guidelines, a total of 2769 titles and abstracts were screened, and 97 papers underwent full-text review. In the final analyses, 15 articles and 12 systematic reviews were included, whereas guidelines are presented as supplementary material. No studies were identified that examined follow-up regarding long-term overall cardiovascular risk after gestational diabetes. Various lifestyle interventions were tested for individual cardiovascular risk factors, with diverging effects. eHealth technologies were found acceptable by participants but had no consistent, statistically significant effect on relevant health outcomes. CONCLUSIONS: This scoping review of the existing literature revealed neither an established systematic cardiovascular follow-up strategy for women after gestational diabetes nor evidence that eHealth technologies are superior to conventional follow-up. Further research into the utility of eHealth in cardiovascular follow-up after complicated pregnancies should include longer-term follow-up and core cardiovascular outcomes. SYSTEMATIC REVIEW REGISTRATION: The protocol for this scoping review was published at Open Science Framework (osf.io/p5hw6).

Circulating angiotensin II type I receptor - autoantibodies in diabetic pregnancies.

Pregnant women with either pre-existing or gestational diabetes mellitus are at increased risk of preeclampsia as well as future cardiovascular disease. The renin-angiotensin system is dysregulated in both diabetes mellitus and preeclampsia. In preeclampsia, maternal levels of circulating agonistic autoantibodies against the angiotensin II Type I receptor (AT1-AAs) are increased. Circulating AT1-AAs are thought to contribute to both the pathophysiology of preeclampsia and the increased risk of future cardiovascular disease. Studies exploring AT1-AA in diabetes outside pregnancy suggest their potential for both metabolic and cardiovascular pathogenicity. No studies have investigated AT1-AAs in diabetic pregnancies. We hypothesized elevated maternal circulating AT1-AA levels in pregnancies complicated by any type of diabetes mellitus. Third-trimester maternal serum from 39 women (controls: n = 10; type 1 diabetes: n = 9; type 2 diabetes: n = 10; gestational diabetes=10) were analyzed for AT1-AA using an established bioassay method. Circulating AT1-AAs were present in 70% (7/10) of the controls and 83% (24/29) of the diabetes group (P = 0.399). Presence of AT1-AA was correlated to hsCRP levels (P = 0.036), but neither with maternal circulating angiogenic factors (soluble fms-like tyrosine kinase-1 and placental growth factor), nor with maternal or fetal characteristics indicative of metabolic disease or placental dysfunction. Our study is the first to demonstrate presence of circulating AT1-AAs in pregnant women with any type of diabetes. Our findings suggest AT1-AAs presence in pregnancy independently of placental dysfunction, nuancing the current view on their pathogenicity. Whether AT1-AAs per se contribute to increased risk of adverse pregnancy outcomes and future cardiovascular disease remains currently unanswered.

Maternal haemodynamics in Hypertensive Disorders of Pregnancy under antihypertensive therapy (HyperDiP): study protocol for a prospective observational case-control study.

INTRODUCTION: Hypertensive disorders of pregnancy (HDP) are associated with a high incidence of maternal and perinatal morbidity and mortality. HDP, in particular pre-eclampsia, have been determined as risk factors for future cardiovascular disease. Recently, the common hypothesis of pre-eclampsia being a placental disorder was challenged as numerous studies show evidence for short-term and long-term cardiovascular changes in pregnancies affected by HDP, suggesting a cardiovascular origin of the disease. Despite new insights into the pathophysiology of HDP, concepts of therapy remain unchanged and evidence for improved maternal and neonatal outcome by using antihypertensive agents is lacking. METHODS AND ANALYSIS: A prospective observational case-control study, including 100 women with HDP and 100 healthy controls, which will assess maternal haemodynamics using the USCOM 1A Monitor and Arteriograph along with cardiovascular markers (soluble fms-like kinase 1/placental-like growth factor, N-terminal pro-B type natriuretic peptide) in women with HDP under antihypertensive therapy, including a follow-up at 3 months and 1 year post partum, will be conducted over a 50-month period in Vienna. A prospective, longitudinal study of cardiovascular surrogate markers conducted in Oslo will serve as a comparative cohort for the Vienna cohort of haemodynamic parameters in pregnancy including a longer follow-up period of up to 3 years post partum. Each site will provide a dataset of a patient group and a control group and will be assessed for the outcome categories USCOM 1A measurements, Arteriograph measurements and Angiogenic marker measurements. To estimate the effect of antihypertensive therapy on outcome parameters, ORs with 95% CIs will be computed. Longitudinal changes of outcome parameters will be compared between normotensive and hypertensive pregnancies using mixed-effects models. ETHICS AND DISSEMINATION: Ethical approval has been granted to all participating centres. Results will be published in international peer-reviewed journals and will be presented at national and international conferences.

Poor glucose control and markers of placental dysfunction correlate with increased circulating fetal microchimerism in diabetic pregnancies.

Fetal microchimerism (FMc) arises during pregnancy as fetal cells enter maternal circulation and remain decades postpartum. Circulating FMc is increased in preeclampsia, fetal growth restriction, and as we recently showed, is associated with biomarkers of placental dysfunction in normotensive term pregnancies. Diabetes mellitus (DM) also correlates with placental dysfunction. We hypothesize that poor glucose control and markers of placental dysfunction are associated with increased circulating FMc in diabetic pregnancies. We included 122 pregnancies preceding active labor (pregestational DM, n = 77, gestational DM (GDM), n = 45) between 2001 and 2017. Maternal and fetal samples were genotyped for various human leukocyte antigen (HLA) loci, and other polymorphisms to identify fetus-specific alleles. We used validated polymerase chain reaction (PCR) assays to quantify FMc in maternal peripheral blood buffy coat. Negative binomial regression with adjustment for confounders was used to assess FMc quantity. In pregestational DM, increased circulating FMc correlated with elevation of HbA1c (≥ 6.0 %) (detection rate ratio (DRR) = 4.9, p = 0.010) and a 1000 pg/mL rise in the anti-angiogenic biomarker soluble fms-like tyrosine kinase-1 (sFlt-1) (DRR = 1.1, p = 0.011). In GDM, increased FMc correlated with elevated 2-hour oral glucose tolerance test results (DRR = 2.3, p = 0.046) and birthweight < 10th or > 90th percentile (DRR = 4.2, p = 0.049). These findings support our novel hypothesis that FMc correlates with poor glucose control and various aspects of placental dysfunction in DM. Whether increased FMc in pregnancies with poor glucose control and placental dysfunction contributes to the risk of preeclampsia in diabetic pregnancies and to the increased risk of chronic cardiovascular disease later in life remains to be investigated.

Fetal microchimerism and the two-stage model of preeclampsia.

Fetal cells cross the placenta during pregnancy and some have the ability to persist in maternal organs and circulation long-term, a phenomenon termed fetal microchimerism. These cells often belong to stem cell or immune cell lineages. The long-term effects of fetal microchimerism are likely mixed, potentially depending on the amount of fetal cells transferred, fetal-maternal histocompatibility and fetal cell-specific properties. Both human and animal data indicate that fetal-origin cells partake in tissue repair and may benefit maternal health overall. On the other hand, these cells have been implicated in inflammatory diseases by studies showing increased fetal microchimerism in women with autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. During pregnancy, preeclampsia is associated with increased cell-transfer between the mother and fetus, and an increase in immune cell subsets. In the current review, we discuss potential mechanisms of transplacental transfer, including passive leakage across the compromised diffusion barrier and active recruitment of cells residing in the placenta or fetal circulation. Within the conceptual framework of the two-stage model of preeclampsia, where syncytiotrophoblast stress is a common pathophysiological pathway to maternal and fetal clinical features of preeclampsia, we argue that microchimerism may represent a mechanistic link between stage 1 placental dysfunction and stage 2 maternal cardiovascular inflammation and endothelial dysfunction. Finally, we postulate that fetal microchimerism may contribute to the known association between placental syndromes and increased long-term maternal cardiovascular disease risk. Fetal microchimerism research represents an exciting opportunity for developing new disease biomarkers and targeted prophylaxis against maternal diseases.