The etiology of recurrent pregnancy loss (RPL) is complex and multifactorial and in half of patients it remains unexplained (U-RPL). Recently, low-molecular-weight heparin (LMWH) has gained increasing relevance for its therapeutic potential. On this regard, the aim of this systematic review and meta-analysis is to analyze the efficacy of low molecular weight heparin (LMWH) from the beginning of pregnancy in terms of live birth rates (LBR) in U-RPL. Registered randomized controlled trials (RCTs) were included. We stratified findings based on relevant clinical factors including number of previous miscarriages, treatment type and control type. Intervention or exposure was defined as the administration of LMWH alone or in combination with low-dose aspirin (LDA). A total of 6 studies involving 1016 patients were included. The meta-analysis results showed that LMWH used in the treatment of U-RPL was not associated with an increase in LBR with a pooled OR of 1.01, a medium heterogeneity (26.42%) and no publication bias. Results of other sub-analyses according to country, treatment type, and control type showed no significant effect of LMWH on LBR in all subgroups, with a high heterogeneity. The results highlight a non-significant effect of LMWH in U-RPL on LBR based on moderate quality evidence.Registration number: PROSPERO: ( https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326433 ).

The article aimed to compare the efficiency and safety of aspirin with low-molecular-weight heparin (LMWH) for thromboprophylaxis in orthopaedic surgery patients. According to the inclusion and exclusion criteria, PubMed, Embase and Cochrane Library database were searched for studies comparing aspirin and LMWH in venous thromboembolism (VTE) prophylaxis until 25 April 2023. The outcome measures included deep venous thrombosis(DVT)/Pulmonary embolism(PE) events, major bleeding events, wound complications, wound infection and death. Six studies met the requirements of our meta-analysis, including 12 470 patients in the aspirin group and 10 857 patients in the LMWH group. The meta-analysis showed that results showed that LMWH was superior to aspirin in preventing VTE events (odds ratio (OR) 1.44, 95% CI 1.24-1.68, P  < 0.00001), whereas there was no significant difference between them in bleeding events (OR 0.95, 95% CI 0.86-1.05, P  = 0.33), wound complication (OR 0.58, 95% CI 0.28-1.17, P  = 0.13), wound infection (OR 1.12, 95% CI 0.86-1.47, P  = 0.39) and mortality (OR 1.04, 95% CI 0.70-1.55, P  = 0.83). In addition, subgroup analysis showed that compared with aspirin, LMWH was more likely to reduce the incidence of DVT events in orthopaedic surgery patients (OR 1.59, 95% CI 1.33-1.91, P  < 0.00001), whereas there was no advantage in reducing the incidence of PE events (OR 1.22, 95% CI 0.62-2.40, P  = 0.56). Despite the similar safety profiles, this meta-analysis showed that LMWH was significantly superior to aspirin in thromboprophylaxis after orthopaedic surgery. LMWH was still the first-line drug for thrombosis prevention in patients who underwent major orthopaedic surgeries.

Asparaginase is essential in the initial management of acute lymphoblastic leukemia (ALL) but frequently leads to venous thromboembolism (VTE). Using anticoagulants for primary VTE prevention has been studied with no consensus. We conducted a systematic literature search in PubMed, Scopus, and Web of science and performed random-effect meta-analysis using Mantel-Haenszel method in RevMan 5.4 to analyze primary pharmacological thromboprophylaxis during asparaginase treatment in early-phase (induction, consolidation, or intensification phase) therapy in patients with ALL with all ages and followed with subgroup analysis by age. Meta-analysis of 13 articles describing the effect of antithrombin supplementation in 1375 patients showed that antithrombin prophylaxis decreases the risk of VTE by 43% (RR, 0.57; 95% CI, 0.38 - 0.83; p=0.004), with mild heterogeneity (I2=35%, p=0.10) and moderate certainty by GRADE. 8 articles included for meta-analysis of low-molecular weight heparin (LMWH) treatment in 612 patients showed that it decreased the risk of VTE by nearly 40% (RR, 0.61; 95% CI, 0.45 - 0.81; p=0.00081), with minimal heterogeneity (I2=14%, p=0.31) but low certainty. Subgroup analysis showed that only prophylaxis with antithrombin supplementation significantly decreased the VTE rate in adult patients with moderate certainty. In pediatric patients, one nonrandomized prospective study showed that LMWH combined with antithrombin has a better thromboprophylaxis effect than antithrombin alone. In the PREVAPIX-ALL trial, prophylaxis with direct factor Xa inhibitor Apixaban did not benefit children younger than 18 years except for cases of obesity. We concluded that thromboprophylaxis with antithrombin is effective in ALL patients older than 18 years during the early phase of therapy, and LMWH combined with antithrombin supplementation might be effective for pediatric patients with ALL. Apixaban is effective in pediatric ALL patients with obesity and needs further study in other high-risk patients.

BACKGROUND: This systematic review and meta-analysis aimed to evaluate the effects of Taohong Siwu Decoction (THSWD) combined with low molecular weight heparin (LMWH), as well as THSWD alone, on the incidence of Deep vein thrombosis (DVT), D-dimer levels, prothrombin time (PT), activated partial thromboplastin time (APTT), visual analogue scale (VAS) pain score, and calf swelling in patients undergoing hip fracture or replacement surgery, compared to LMWH.
METHODS: According to the predefined inclusion criteria, we conducted a comprehensive search for randomized controlled trials (RCTs) examining the efficacy of THSWD combined with LMWH or THSWD compared to LMWH in patients with hip fractures or undergoing replacement surgery. The search was performed across multiple databases including China National Knowledge Internet, WanFang, Sinomed, Duxiu, PubMed, Embase, Google Scholar, Cochrane, and Web of Science from their inception until December 2023. Additionally, relevant literature references were retrieved and hand searching of pertinent journals was conducted. The methodological quality assessment of the included trials was carried out following the guidelines outlined in the Cochrane Handbook. Review Manager 5.4 was applied in analyzing and synthesizing.
RESULTS: A total of 18 RCTs with 1353 patients were included. The results of meta-analysis showed that compared with the control group, the combined group had a better effect on the incidence of DVT [RR = 0.32, 95% CI(0.17, 0.58; P = .0002], D-dimer [SMD = -5.88, 95% CI(-7.66, -4.11); P < .00001], VAS [MD = -1.16, 95% CI(-1.81, -0.50); P = .0005], Calf circumference difference [MD = -0.56, 95% CI(-1.05, -0.08); P = .02]. There was no significant difference in PT and APTT between the combined group and the control group. Meta-analysis results show that the D-dimer, incidence of DVT, PT, and APTT did not significantly differ between the THSWD and the LMWH groups.
CONCLUSIONS: This meta-analysis shows that compared with LMWH, THSWD combined with LMWH has a better efficacy in the treatment of DVT after hip surgery, without a significant increase in the incidence of adverse events. Additionally, the combined therapy can also reduce D-dimer, VAS, and swelling. However, due to the limitations of the included studies (such as small sample size and low-quality evidence), the results need to be further verified in more rigorous multicenter clinical trials with a large sample size.

BACKGROUND: Direct oral anticoagulants (DOACs) used as an alternative to low-molecular-weight heparin (LMWH) for thromboprophylaxis after cancer surgery for venous thromboembolic events (VTE) remains unclear. This study aimed to investigate the efficacy and safety of DOACs versus LMWH in these patients.
METHODS: A search of EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science was carried out and included all randomized controlled trials (RCTs) and observational studies that directly compared DOACs with LMWH for thromboprophylaxis in patients after cancer surgery through July 25, 2023. The primary efficacy and safety outcomes were VTE, major bleeding, and clinically relevant non-major bleeding (CRNMB) within 30 days of surgery. The risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB2) tool for RCTs and ROBINS-I tool for non-randomized studies. This study was registered in PROSPERO (CRD42023445386).
RESULTS: We retrieved 5149articles, selected 27 for eligibility, and included 10 studies (three RCTs and seven observational studies) encompassing 3054 patients who underwent postoperative thromboprophylaxis with DOACs (41%) or LMWH (59%). Compared to LMWH thromboprophylaxis, DOACs had a comparable risk of VTE (RR:0.69[95% CI:0.46-1.02], I2 = 0%), major bleeding (RR:1.55 [95% CI:0.82-2.93], I2 = 2%), and CRNMB (RR, 0.89 [95% CI, 0.4-1.98], I2 = 31%) during the 30-day postoperative period. Subgroup analysis of VTE and major bleeding suggested no differences according to study type, extended thromboprophylaxis, tumor types, or different types of DOAC.
CONCLUSIONS: DOACs are potentially effective alternatives to LMWH for thromboprophylaxis in patients undergoing cancer surgery, without increasing the risk of major bleeding events.

BACKGROUND: The use of direct oral anticoagulants (DOACs) as an alternative to low-molecular-weight heparin (LMWH) for extended thromboprophylaxis of abdominal/pelvic cancer-related postoperative thromboembolism (VTE) is unclear. We aim to investigate the efficacy and safety of DOACs vs. LMWH in these patients.
METHODS: A systematic review was conducted using EMBASE, MEDLINE, CENTRAL, and Web of science through May 19th, 2023 for all randomized controlled trials (RCTs) and observational studies that compared the outcomes with DOACs vs. LMWH for extended thromboprophylaxis among patients undergoing abdominal/pelvic cancer surgery. Primary efficacy outcome was clinical VTE, and safety outcome was clinically relevant bleeding complications reported within the 30-day postoperative period. This study was registered in PROSPERO (CRD42023413175).
RESULTS: We identified 5078 articles and selected 29 full-text articles for eligibility. A total of 9 studies (2 RCTs and 7 observational studies) encompassing 2651 patients were included for systematic review and 7 for meta-analysis. When compared with LMWH extended thromboprophylaxis, DOACs had a similar incidence of VTE (RR: 0.65 [95% CI: 0.32-1.33], I2 = 0%), major bleeding (RR: 1.68 [95% CI: 0.36-7.9], I2 = 26%), and clinically relevant non-major bleeding (RR: 0.68 [95% CI: 0.39-1.19], I2 = 0%). Subgroup analysis suggested no difference according to the study type (RCTs versus observational studies) regarding clinical VTE or major bleeding (Pinteraction = 0.43 and Pinteraction = 0.71, respectively).
CONCLUSIONS: Our results suggest that DOACs for extended thromboprophylaxis were an effective and safe alternative to LMWH after major abdominal/pelvic cancer-related surgery.

OBJECTIVE: To systematically evaluate the efficacy of low molecular weight heparin (LMWH) to prevent preeclampsia in high risk pregnant women without thrombophilia.
METHODS: PubMed, Embase and the Cochrane library were searched for articles published before 1st August 2022 using the combination keywords \"preeclampsia\", \"Low Molecular Weight Heparin\", \"LMWH\", \"Heparin, Low Molecular Weight\", \"Dalteparin\", \"Nadroparin\", and \"Tinzaparin\".
METHODS: Randomized controlled trials evaluating the use of LMWH in pregnant women at high risk of preeclampsia without thrombophilia.
METHODS: Ten studies were included in the meta-analysis (1758 patients in total). Outcomes were expressed as relative risk (RR) with 95% confidence intervals (CI).
RESULTS: LMWH reduced the incidence of PE (RR = 0.67; 95% CI = 0.50-0.90; P = 0.009) in high risk pregnant women without thrombophilia. Subgroup analysis found that the prophylactic effect of LMWH was only significant in studies using low-dose aspirin (LDA) as the primary intervention. The combination of LMWH and LDA was also effective for the prevention of preterm birth and fetal growth restriction, but had no effect on the incidence of placenta abruption.
CONCLUSIONS: For women at high risk of developing preeclampsia without thrombophilia, the combination of LMWH and low-dose aspirin is effective for the prevention of preeclampsia, preterm birth and fetal growth restriction and is superior to LDA alone.

Cerebral venous thrombosis is a rare cause of stroke in young mostly female adults which is frequently overlooked due to its variable clinical and radiological presentation. This review summarizes current knowledge on it risk factors, management and outcome in adults and highlights areas for future research. Females are 3 times more commonly affected and are significantly younger than males. The presenting symptoms can range from headache to loss of consciousness. However, the often-nebulous nature of symptoms can make the diagnosis challenging. Magnetic resonance imaging with venography is often the diagnostic imaging of choice. While unfractionated or low molecular-weight heparin is the mainstay of treatment, endovascular intervention with thrombolysis or thrombectomy and decompressive craniectomy may be required depending on clinical status. Nevertheless, approximately 80% of patients have a good recovery but mortality rates of -5% to 10% are not uncommon. Diagnosing cerebral venous thrombosis can be challenging but with vigilance and expert care patients have the best chance of a good clinical outcome.

UNASSIGNED: Venous thromboembolism (VTE) can occur in children with COVID-19, and the efficacy and safety of prophylactic anticoagulant therapy are uncertain. This study aimed to assess the incidence of VTE in pediatric patients with COVID-19, the association of D-dimer with thrombus formation, and the effectiveness and safety of prophylactic anticoagulation treatment.
UNASSIGNED: We systematically searched databases from January 2020 to February 2023. A systematic review and meta-analysis were conducted to determine the incidence of VTE in children and evaluate the efficacy and safety of prophylactic anticoagulant therapy.
UNASSIGNED: Thirteen cohort studies and one clinical trial were included. The pooled incidence rate of VTE in affected children was 1.5% (95% CI 0.4-2.9%). Children with D-dimer levels five times higher than normal had a higher risk of VTE (OR 4.92, 95% CI 1.60-15.11). Prophylactic anticoagulant therapy did not significantly reduce the risk of VTE (OR 1.35, 95% CI 0.74-2.49). The safety of prophylactic anticoagulant therapy was relatively high, with major bleeding and all-cause mortality rates below 0.1% (95% CI 0.0-0.2%).
UNASSIGNED: The incidence of VTE in children with COVID-19 is low, and prophylaxis based on ISTH standards is reasonable. Low-molecular-weight heparin (LMWH) for VTE prevention has a high level of safety. However, more high-quality studies are needed to understand the impact of anticoagulant therapy on VTE incidence in pediatric patients with COVID-19.

BACKGROUND: The safety and efficacy of direct-acting oral anticoagulants (DOACs) for therapeutic anticoagulation in the setting of primary or metastatic brain cancer is not known.
OBJECTIVE: To conduct a meta-analysis and systematic review of studies that compare the risk of intracranial hemorrhage (ICH) in patients with brain cancer treated with DOACs vs low-molecular-weight heparin (LMWH).
METHODS: A literature search was conducted using PubMed, EMBASE, and Cochrane databases. Summary statistics were obtained by calculating the risk ratio (RR), and heterogeneity across studies was estimated using the I2 statistic. A total of 10 retrospective studies (n = 1638) met criteria for inclusion. The primary endpoint was the pooled RR for ICH in patients with brain tumors receiving anticoagulation with DOACs compared with those receiving LMWH. Secondary analyses included the risk of fatal ICH in each subgroup.
RESULTS: The pooled RR for ICH in patients receiving DOACs vs those receiving LMWH was 0.65 (95% CI, 0.36-1.17; P = .15; I2 = 50%). In studies evaluating primary brain cancer, there was a reduction in risk of ICH with DOACs (RR, 0.35; 95% CI, 0.18-0.69; P = .003; I2 = 0%). In patients with metastatic brain cancer, there was no difference in the risk of ICH with the type of anticoagulation (RR, 1.05; 95% CI, 0.71-1.56; P = .80; I2 = 0%). The overall risk of fatal ICH was not different between anticoagulants.
CONCLUSIONS: The risk of ICH in patients with brain cancer receiving therapeutic anticoagulation varies by anticoagulation agent and diagnosis of primary or metastatic disease.