Risk factors for preterm birth: an umbrella review of meta-analyses of observational studies.

BACKGROUND: Preterm birth defined as delivery before 37 gestational weeks is a leading cause of neonatal and infant morbidity and mortality. The aim of this study is to summarize the evidence from meta-analyses of observational studies on risk factors associated with PTB, evaluate whether there are indications of biases in this literature, and identify which of the previously reported associations are supported by robust evidence. METHODS: We searched PubMed and Scopus until February 2021, in order to identify meta-analyses examining associations between risk factors and PTB. For each meta-analysis, we estimated the summary effect size, the 95% confidence interval, the 95% prediction interval, the between-study heterogeneity, evidence of small-study effects, and evidence of excess-significance bias. Evidence was graded as robust, highly suggestive, suggestive, and weak. RESULTS: Eighty-five eligible meta-analyses were identified, which included 1480 primary studies providing data on 166 associations, covering a wide range of comorbid diseases, obstetric and medical history, drugs, exposure to environmental agents, infections, and vaccines. Ninety-nine (59.3%) associations were significant at P < 0.05, while 41 (24.7%) were significant at P < 10-6. Ninety-one (54.8%) associations had large or very large heterogeneity. Evidence for small-study effects and excess significance bias was found in 37 (22.3%) and 12 (7.2%) associations, respectively. We evaluated all associations according to prespecified criteria. Seven risk factors provided robust evidence: amphetamine exposure, isolated single umbilical artery, maternal personality disorder, sleep-disordered breathing (SDB), prior induced termination of pregnancy with vacuum aspiration (I-TOP with VA), low gestational weight gain (GWG), and interpregnancy interval (IPI) following miscarriage < 6 months. CONCLUSIONS: The results from the synthesis of observational studies suggest that seven risk factors for PTB are supported by robust evidence. Routine screening for sleep quality and mental health is currently lacking from prenatal visits and should be introduced. This assessment can promote the development and training of prediction models using robust risk factors that could improve risk stratification and guide cost-effective preventive strategies. TRIAL REGISTRATION: PROSPERO 2021 CRD42021227296.

Regulatory T cells in the peripheral blood of women with gestational diabetes: a systematic review and meta-analysis.

Background: Gestational diabetes (GDM) affects approximately 14% of pregnancies globally and is associated with short- and long-term complications for both the mother and child. In addition, GDM has been linked to chronic low-grade inflammation with recent research indicating a potential immune dysregulation in pathophysiology and a disparity in regulatory T cells. Objective: This systematic review and meta-analysis aimed to determine whether there is an association between GDM and the level of Tregs in the peripheral blood. Methods: Literature searches were conducted in PubMed, Embase, and Ovid between the 7th and 14th of February 2022. The inclusion criteria were any original studies published in the English language, measuring differentiated Tregs in women with GDM compared with glucose-tolerant pregnant women. Meta-analysis was performed between comparable Treg markers. Statistical tests were used to quantify heterogeneity: τ 2, χ 2, and I 2. Study quality was assessed using a modified version of the Newcastle-Ottawa scale. Results: The search yielded 223 results: eight studies were included in the review and seven in the meta-analysis (GDM = 228, control = 286). Analysis of Tregs across all trimesters showed significantly lower Treg numbers in women with GDM (SMD, -0.76; 95% CI, -1.37, -0.15; I 2 = 90%). This was reflected in the analysis by specific Treg markers (SMD -0.55; 95% CI, -1.04, -0.07; I 2 = 83%; third trimester, five studies). Non-significant differences were found within subgroups (differentiated by CD4+FoxP3+, CD4+CD127-, and CD4+CD127-FoxP3) of both analyses. Conclusion: GDM is associated with lower Treg numbers in the peripheral maternal blood. In early pregnancy, there is clinical potential to use Treg levels as a predictive tool for the subsequent development of GDM. There is also a potential therapeutic intervention to prevent the development of GDM by increasing Treg populations. However, the precise mechanism by which Tregs mediate GDM remains unclear. Systematic review registration: https://www.crd.york.ac.uk/prospero, identifier CRD42022309796.

Pregnancy physical activity questionnaire: Translation and cross-cultural adaptation of a Greek version.

OBJECTIVE: The aim of this study was to translate and adapt the Pregnancy Physical Activity Questionnaire (PPAQ) into Greek culture. STUDY DESIGN: The procedure followed to translate the PPAQ included the stages: forward translation, synthesis, backward translation and an expert committee review. Members of the research team discussed ambiguities, discordances and equivalence at each stage. Then, the pre-final Greek version of the PPAQ was pre-tested on 46 pregnant women; a quantitative and qualitative analysis was conducted. RESULTS: Few modifications were done to the original PPAQ, in order to ensure cultural adaptation and clinical implementation. Appropriate changes to the international metric units were done. In addition, two items have been modified to achieve relevance with Greek culture. Two items were merged into one and three items were splitted, which maintained their initial meaning. Those changes were made to match the energy expenditure compendium update for physical activities. Participants at the pre-test had a mean age of 34,23 years, response time to the questionnaire varied between 5 and 10 min and there were no missing data. No difficulties or misunderstandings were reported by the participants during pre-testing. Thus, the research team agreed on the pre-final PPAQ Greek version. CONCLUSION: The final PPAQ Greek version indicated transcultural equivalence to the original PPAQ in English. It is also a unique questionnaire for assessing physical activity in Greek pregnant women and will be a useful tool in clinical routine.

Risk factors for preterm labor: An Umbrella Review of meta-analyses of observational studies.

Preterm birth defined as delivery before 37 gestational weeks, is a leading cause of neonatal and infant morbidity and mortality. Understanding its multifactorial nature may improve prediction, prevention and the clinical management. We performed an umbrella review to summarize the evidence from meta-analyses of observational studies on risks factors associated with PTB, evaluate whether there are indications of biases in this literature and identify which of the previously reported associations are supported by robust evidence. We included 1511 primary studies providing data on 170 associations, covering a wide range of comorbid diseases, obstetric and medical history, drugs, exposure to environmental agents, infections and vaccines. Only seven risk factors provided robust evidence. The results from synthesis of observational studies suggests that sleep quality and mental health, risk factors with robust evidence should be routinely screened in clinical practice, should be tested in large randomized trial. Identification of risk factors with robust evidence will promote the development and training of prediction models that could improve public health, in a way that offers new perspectives in health professionals.

Suspected twin anemia polycythemia sequence in a dichorionic, diamniotic twin pregnancy: a case report.

BACKGROUND: Twin anemia polycythemia sequence is a rare complication in monochorionic twin pregnancy. CASE PRESENTATION: We describe a case of dichorionic twin pregnancy presenting with suspected twin anemia polycythemia sequence. A 31-year-old White female, on her third pregnancy, had a routine ultrasound scan at 12 weeks gestation, which demonstrated a dichorionic twin pregnancy with one placenta located in the anterior wall and the other in the posterior wall of the uterus. At 21 weeks, a scan demonstrated a 24% growth discordance between the two fetuses with normal Doppler studies and amniotic fluid. At 27 weeks, one twin showed signs of anemia and the other polycythemia; the fetal middle cerebral artery peak systolic velocity was high in the anemic fetus and low in the polycythemic twin (1.8 and 0.5 multiples of the median). An intrauterine blood transfusion was carried out and this increased the fetal hemoglobin concentration in the anemic twin from 3.5 to 12.5 g/dL. At 29 weeks, delivery by cesarean section was carried out because of evidence from middle cerebral artery peak systolic velocity of recurrence of anemia in one twin and worsening polycythemia in the co-twin; at birth the hemoglobin concentrations were 5.6 and 24.9 g/dL, respectively. Histopathological examination confirmed dichorionicity with no communicating vessels between the two placentas. CONCLUSIONS: This is the first case of twin anemia polycythemia sequence in a dichorionic, diamniotic twin pregnancy where intrauterine blood transfusion was used to prolong the pregnancy by almost 2 weeks in a "twin anemia polycythemia sequence-like" setting.

Isolation and freezing of human peripheral blood mononuclear cells from pregnant patients.

To analyze immune cell populations accurately, a large number of Peripheral Blood Mononuclear Cells (PBMCs) must be obtained from blood samples. Traditional manual isolation and SepMateTM isolation of PBMCs consistently yield blood-stained plasma layers and overall low numbers of CD4+ and CD8+ cells. Here, we describe an optimized protocol, using PBS with EDTA to increase PBMC yield from pregnant patients. This protocol enables analysis of CD4+, CD8+, and Regulatory T Cells and is potentially applicable to any immune cell population. For complete details on the use and execution of this protocol, please refer to the SepMateTM website https://www.stemcell.com/products/brands/SepMateTM-pbmc-isolation.html.

Progressive multifocal leukoencephalopathy in the context of newer therapies in hematology and review of new treatment strategies.

Progressive multifocal leukoencephalopathy (PML) is a rare, often fatal demyelinating disease of the central nervous system (CNS) caused by the reactivation of JC polyomavirus in the CNS. We present a case of a 54-year-old man with follicular lymphoma diagnosed with PML after being treated with anti-CD20 monoclonal antibody-based regimens for several years. Due to the lack of effective treatment choices for PML, the patient was treated with nivolumab, based on recent reports, but succumbed to his disease a few months after diagnosis. In this paper, we focus on reviewing the literature of PML cases correlated with newer agents used in hematology, possible factors affecting disease prognosis, as well as the available data on upcoming therapeutic options for patients with PML. Though newer promising treatments such as anti-PD1 monoclonal antibodies arise, a definitive treatment option is yet to be found. Vigilance, early detection, and prompt intervention play a crucial role in the prognosis of PML in patients with hematological malignancies.

Regulatory T Cells in Pregnancy Adverse Outcomes: A Systematic Review and Meta-Analysis.

Background: Several studies report the role of Regulatory T-cells (Tregs) in the pathophysiology of pregnancy adverse outcomes. Objective: The aim of this systematic review and meta-analysis was to determine whether there is an association between regulatory T cell levels and pregnancy adverse outcomes (PAOs), including pre-eclampsia and preterm birth (PTB). Method: Literature searches were conducted in PubMed/MEDLINE, Embase, and Cochrane CENTRAL databases. Inclusion criteria were original articles (clinical trials, case-control studies and cohort studies) comparing Tregs, sampled from the decidua or maternal blood, in healthy pregnant women versus women with pre-eclampsia or PTB. The outcome was standardised mean difference (SMD) in Treg numbers. The tau-squared (Tau²), inconsistency index (I²), and chi-squared (χ²) test quantified heterogeneity among different studies. Analyses were performed in RevMan software V.5.4.0 for Mac using a random-effects model with outcome data reported with 95% confidence intervals (CI). This study was prospectively registered with PROSPERO (CRD42020205469). PRISMA guidelines were followed. Results: From 4,085 unique studies identified, 36 were included in qualitative synthesis, and 34 were included in quantitative synthesis (meta-analysis). In total, there were 1,783 participants in these studies: healthy controls=964, pre-eclampsia=759, PTB=60. Thirty-two studies compared Tregs in healthy pregnant women and women with pre-eclampsia, and 30 of these sampled Tregs from peripheral blood showing significantly higher Treg numbers in healthy pregnancies (SMD; 1.46; 95% CI, 1.03-1.88; I²=92%). Four studies sampled Tregs from the maternal decidua showing higher Tregs in healthy pregnancies (SMD, 0.76; 95% CI, -0.13-1.65; I²=84%). No difference was found in the number of Tregs between early versus late pre-eclampsia (SMD,-1.17; 95% CI, -2.79-0.44; I²=94%). For PTB, two studies compared Tregs sampled from the peripheral blood with a tendency for higher Tregs in healthy pregnancies but this did not reach significance (SMD, 2.18; 95% CI, -1.34-5.70; I²=96%). Subcohort analysis using Treg analysis (flow cytometry vs. qPCR vs. immunofluorescence tissue staining) showed similar associations. Conclusion: Lower Tregs in pregnancy, sampled from the maternal peripheral blood, are associated with pre-eclampsia. There is a need for further studies to confirm a relationship between low Tregs and PTB. As the precise mechanisms by which Tregs may mediate pre-eclampsia and PTB remain unclear, further fundamental research is necessary to elucidate the underlying processes and highlight the causative link. Systematic Review Registration: PROSPERO, identifier CRD42020205469.

Emergency cerclage in singleton pregnancies with painless cervical dilatation: A meta-analysis.

INTRODUCTION: Emergency cerclage is the most common active intervention in pregnant women with cervical insufficiency. This meta-analysis aimed to compare the effectiveness of emergency cerclage vs expectant management on maternal and perinatal outcomes, and to assess the current status of evidence. MATERIAL AND METHODS: A search was conducted from 1 June 2019 until 1 September 2019 and eligible studies were identified in the MEDLINE, Scopus, Cochrane and US clinical trials registry without limitations concerning the publication dates and languages. Randomized controlled trials (RCTs), non-RCTs and observational studies comparing emergency cerclage with no cerclage/expectant management, in women presenting with painless cervical dilatation were included. RESULTS: The electronic search yielded 3607 potential studies, of which 38 were fully reviewed and 12 observational studies (1021 participants) were included. Cerclage was superior to expectant management for the primary outcomes of preterm birth before 28 and 32 gestational weeks, OR 0.25 (95% CI 0.16-0.39, five studies, N = 392, I2 = 41%, low quality) and 0.08 (95% CI 0.02-0.29, four studies, N = 176, I2 = 51%, low quality), respectively. Cerclage was also superior to expectant management for the secondary outcomes of fetal loss OR 0.26 (95% CI 0.12-0.56, 8 studies, N = 455, I2 = 46%, very low-quality), pregnancy prolongation in days mean difference 47.45 (95% CI 39.89-55.0, 12 studies, N = 1027 I2 = 86%, very low quality), gestational age at birth in weeks mean difference 5.68 (95% CI 4.69-6.67, 9 studies, N = 892, I2 = 73%, very low quality), admission to neonatal intensive care OR 0.21 (95% CI 0.07-0.70, two studies, N = 79, I2 = 36%, very low quality) and neonatal death OR 0.12 (95% CI 0.04-0.34, five studies, N = 130, I2 = 0%, very low quality). There were no differences between cerclage and expectant management concerning premature rupture of membranes during or after the procedure OR 0.68 (95% CI 0.31-1.48, two studies, N = 155, I2 = 85%, very low quality) and chorioamnionitis OR 1.14 (95% CI 0.31-4.25, three studies, N = 88, I2 = 33%, very low quality). CONCLUSIONS: Emergency cerclage in pregnant women with painless cervical dilatation seems to decrease preterm births, prolong the pregnancy, and decrease the neonatal deaths and fetal losses, but does not increase the risk of chorioamnionitis and premature rupture of membranes. Despite the extremely favorable estimates for cerclage, the results should be viewed with caution because, as a result of the lack of randomized control trials, the quality of evidence is low to very low.

Gabapentin monotherapy for the treatment of chemotherapy-induced neuropathic pain: a pilot study.

OBJECTIVE: This study was conducted to investigate the efficacy and safety of gabapentin monotherapy in the management of chemotherapy-induced neuropathic pain. PATIENTS: Seventy-five cancer patients who had previously received chemotherapy, and had experienced at least one symptom of neuropathic pain were included in the intervention group. They received a fixed low-dose of gabapentin (800 mg/day). The control group consisted of 35 cancer patients with similar treatment history and symptomatology, who refused treatment with gabapentin and, therefore, received a fixed-dose combination of naproxen and codeine/paracetamol. OUTCOME MEASURES: Patients were grouped in three categories according to the severity of their neuropathic symptoms at baseline: mild, moderate, and severe. Analgesic efficacy of the study drug was assessed by means of a patient-answered questionnaire. Four stages of analgesic response were established: complete, partial, minor, and no response. RESULTS: All patients completed the study and were evaluable. In the intervention arm, gabapentin led to a complete response in 25.3% of patients (19/75), partial response in 44% (33/75), minor response in 25.3% (19/75), and no response in 5.3% (4/75). The response to gabapentin correlated with the severity of the underlying neurotoxicity. Approximately 25% of patients receiving gabapentin experienced mild somnolence, but none discontinued it. In the control group, none experienced complete response (0/35), while partial, minor, and no response were observed in 5.7% (2/35), 45.7% (16/35), and 48.6% (17/35), respectively. Compared with the control group, gabapentin therapy led to a statistically significant better response in patients of each baseline neurotoxicity group. CONCLUSIONS: Gabapentin monotherapy seems to be well tolerated and useful for the management of chemotherapy-induced neuropathic pain.

Helicobacter pylori infection as an environmental risk factor for migraine without aura.

Helicobacter pylori (H. pylori) infection has recently been associated with various extraintestinal pathologies and migraine. The aim of this study was to investigate the correlation of the H. pylori infection with the pathogenesis of migraine without aura, especially in cases not affected by endogenous risk factors, like hereditary pattern or hormonal fluctuations.A total of 49 outpatients (37 females and 12 males; age range: 19-47 years; mean age: 31,+/-14 years) affected by migraine without aura was evaluated. We divided them in 2 subgroups: a) with positive familial history, and/or with menstrual type of migraine b) with negative familial history and with menstrual unrelated type of migraine. H. pylori infection was diagnosed by the 13 C- urea breath test (INFAI - test). Control subjects consisted of 51 patients without any primary headache history (38 females; mean age of 32,+/-14,4 years; range 21-49 years), who underwent upper gastrointestinal (GI) endoscopy for investigation of anaemia or non ulcer dyspepsia. H. pylori detection was based on the histologic analysis of gastric mucosa biopsy. The prevalence of H. pylori infection was significantly higher in the migraineurs without aura compared to controls (p=0.016). The prevalence of H. pylori infection was significantly high in the mixed and in the female group of our patients without other predisposing factors for migraine without aura (81 and 87% respectively), while in the same groups with predisposing factors (menstruation and/or family history) the prevalence was only 36 and 37% respectively (p=0,001 for the first group and p=0,002 for the second group). Our results seem to highlight the role of H. pylori infection as a probable independent environmental risk factor for migraine without aura, especially in patients that are not genetically or hormonally susceptible to migraine.