The role of low molecular weight heparin on recurrent pregnancy loss: A systematic review and meta-analysis

The effect and mechanism of low-molecular-weight heparin on the decidualization of stromal cells in early pregnancy

OBJECTIVE

This study aimed to analyze the effect of low-molecular-weight heparin (LMWH) on the decidualization of stromal cells in early pregnancy and explore the effect of LMWH on pregnancy outcomes.

METHODS

Recurrent spontaneous abortion (RSA) mouse model (CBA/J × DBA/2) and normal pregnant mouse model (CBA/J × BALB/c) were established. The female mice were checked for a mucus plug twice daily to identify a potential pregnancy. When a mucus plug was found, conception was considered to have occurred 12 h previously. The pregnant mice were divided randomly into a normal pregnancy control group, an RSA model group, and an RSA + LMWH experimental group (n = 10 mice in each group). Halfway through the 12th day of pregnancy, the embryonic loss of the mice was observed; a real-time quantitative polymerase chain reaction was used to detect the messenger ribonucleic acid (mRNA) expressions of prolactin (PRL) and insulin-like growth factor-binding protein 1 (IGFBP1) in the decidua of the mice. Additionally, the decidual tissues of patients with RSA and those of normal women in early pregnancy who required artificial abortion were collected and divided into an RSA group and a control group. Decidual stromal cells were isolated and cultured to compare cell proliferation between the two groups, and cellular migration and invasion were detected by membrane stromal cells. Western blotting was used to detect the protein expressions of proliferating cell nuclear antigen (PCNA), cyclin D1, matrix metalloproteinase- (MMP) 2, and MMP-7 in stromal cells treated with LMWH.

RESULTS

Compared with the RSA group, LMWH significantly reduced the pregnancy loss rate in the RSA mice (p < 0.05). Compared with the RSA group, the LMWH + RSA group had significantly higher expression levels of PRL and IGFBP1 mRNA (p < 0.01). LMWH promoted the proliferation, migration, and invasion of human decidual stromal cells; compared with the control group, the expression levels of MMP-2, MMP-7, cyclin D1, and PCNA proteins in the decidual stromal cells of the LMWH group increased (p < 0.05).

CONCLUSIONS

The use of LMWH can improve pregnancy outcomes by enhancing the proliferation and migration of stromal cells in early pregnancy and the decidualization of stromal cells.

Values and preferences towards the use of prophylactic low-molecular-weight heparin during pregnancy: a convergent mixed-methods secondary analysis of data from the decision analysis in shared decision making for thromboprophylaxis during pregnancy (DASH-TOP) study

BACKGROUND

Venous thromboembolism (VTE) in pregnancy is a major cause of maternal morbidity and mortality, and the use of preventive low-molecular-weight heparin (LMWH) can be challenging. Clinical guidelines recommend eliciting pregnant individuals' preferences towards the use of daily injections of LMWH and discussing the best option through a shared decision-making (SDM) approach. Our aim was to identify individuals' preferences concerning each of the main clinical outcomes, and categorize attributes influencing the use of LMWH during pregnancy.

METHODS

Design: Convergent mixed-methods.

PARTICIPANTS

Pregnant women or those planning a pregnancy with VTE recurrence risk.

INTERVENTION

A SDM intervention about thromboprophylaxis with LMWH in pregnancy.

ANALYSIS

Quantitatively, we report preference scores assigned to each of the health states. Qualitatively, we categorized preference attributes using Burke's pentad of motives framework: act (what needs to be done), scene (patient's context), agent (perspectives and influence of people involved in the decision), agency (aspects of the medication), and purpose (patient's goals). We use mixed-method convergent analysis to report findings using side-by-side comparison of concordance/discordance.

RESULTS

We comprehensively determined preferences for using LMWH by pregnant individuals at risk of VTE: through value elicitation exercises we found that the least valued health state was to experience a pulmonary embolism (PE), followed by major obstetrical bleeding (MOB), deep vein thrombosis (DVT), and using daily injections of LMWH (valued as closest to a 'healthy pregnancy'); through interviews we found that: previous experiences, access to care (scene) and shared decision-making (agent) affected preferences. LMWH's benefits were noted, but substantial drawbacks were described (agency). For participants, the main goal of using LMWH was avoiding any risks in pregnancy (purpose). Side-by-side comparisons revealed concordance and discordance between health states and motives.

CONCLUSIONS

Mixed-methods provide a nuanced understanding of LMWH preferences, by quantifying health states preferences and exploring attributes qualitatively. Incorporating both methods may improve patient-centered care around preference-sensitive decisions in thromboprophylaxis during pregnancy.

A disproportionality analysis of low molecular weight heparin in the overall population and in pregnancy women using the FDA adverse event reporting system (FAERS) database

Background

Low molecular weight heparin (LMWH) is extensively utilized as an anticoagulant for the prevention and management of various thrombotic conditions. However, despite the widespread use of LMWH in clinical indications, its adverse events (AEs) have not received substantial attention, and there is a lack of systematic and comprehensive AE studies. This study aims to evaluate AE signals associated with LMWH in the overall population and in pregnancy women from the FDA Adverse Event Reporting System database.

Methods

We used the Standardized MedDRA Query to identify pregnancy-related AE reports. Disproportionality analyses were employed to identify LMWH-related AE by calculating the reporting odds ratios (ROR), proportional reporting ratios (PRR), bayesian confidence propagation neural network (BCPNN), and the empirical Bayesian geometric mean (EBGM).

Results

For the overall population, the significantly reported adverse signals in SOCs were pregnancy, puerperium, and perinatal conditions, vascular disorders, blood and lymphatic system disorders, and product issues. The five strongest AEs signal of LMWH-related were anti factor X antibody positive (n = 6, ROR 506.70, PRR 506.65, IC 8.31, EBGM 317.03), heparin-induced thrombocytopenia test positive (n = 19, ROR 263.10, PRR 263.02, IC 7.65, EBGM 200.79), anti factor X activity increased (n = 10, ROR 255.93, PRR 255.89, IC 7.62, EBGM 196.61), heparin-induced thrombocytopenia test (n = 14, ROR 231.85, PRR 231.80, IC 7.51, EBGM 182.09), and spontaneous heparin-induced thrombocytopenia syndrome (n = 3, ROR 230.31, PRR 230.30, IC 7.50, EBGM 181.16). For pregnancy women, the five strongest AEs signals of LMWH-related included sternal fracture (n = 3, ROR 243.44, PRR 243.35, IC 6.61, EBGM 97.94), syringe issue (n = 12, ROR 97.49, PRR 97.34, IC 5.94, EBGM 61.21), bleeding time prolonged (n = 3, ROR 97.38, PRR 97.34, IC 5.94, EBGM 61.21), spinal compression fracture (n = 10, ROR 90.24, PRR 90.13, IC 5.87, EBGM 58.30), and injection site haematoma (n = 19, ROR 79.23, PRR 79.04, IC 5.74, EBGM 53.47). Additionally, unexpected AEs associated with LMWH in pregnancy women were observed, including premature baby death, placental necrosis, abortion, antiphospholipid syndrome, systolic dysfunction, compartment syndrome, body height decreased, rubella antibody positive, and ultrasound doppler abnormal.

Conclusion

This study identified unexpected AE signals of LMWH-relate in pregnancy women. Our study could provide valuable evidence for the clinical practice of LMWH, especially for identifying AEs and ensuring safe usage in pregnancy women.

Low-molecular-weight heparin and preeclampsia - does the sword cut both ways? Three case reports and review of literature

BACKGROUND

Low-molecular-weight heparins (LMWH) are the most commonly used anticoagulants during pregnancy. It is considered to be the drug of choice due to its safety in not crossing placenta. Considering the beneficial effect in the improvement of microcirculation, prophylactic application of LMWH in patients with preeclampsia became a trend. However, the bleeding risk related with LMWH in preeclampsia patients has seldomly been evaluated. This current study aimed to identify the potential risks regarding LMWH application in patients with preeclampsia.

CASE SUMMARY

Herein we present a case series of three pregnant women diagnosed with preeclampsia on LMWH therapy during pregnancy. All the cases experienced catastrophic hemorrhagic events. After reviewing the twenty-one meta-analyses, the bleeding risk related with LMWH seems ignorable. Only one study analyzed the bleeding risk of LMWH and found a significantly higher risk of developing PPH in women receiving LMWH. Other studies reported minor bleeding risks, none of these were serious enough to stop LMWH treatment. Possibilities of bleeding either from uterus or from intrabdominal organs in preeclampsia patients on LMWH therapy should not be ignored. Intensive management of blood pressure even after delivery and homeostasis suture in surgery are crucial.

CONCLUSION

Consideration should be given to the balance between benefits and risks of LMWH in patients with preeclampsia.

A Successful Pregnancy Outcome After Continued Surveillance of Lupus Anticoagulant Antibodies in a Patient With Recurrent Pregnancy Loss: A Case Report and Literature Review

Recurrent pregnancy loss (RPL) can be a devastating experience for individuals trying to have children. Various potential causes contribute to the multifactorial pathogenesis of RPL, including chromosomal anomalies, endocrine conditions, autoimmunity, thrombophilias, and infectious agents. Antinuclear antibodies (ANAs) offer an unspecific clue to the underlying autoimmune pathogenic etiology of RPL. This case details a 40-year-old female with a history of RPL, fibromyalgia, and ANA positivity, who spontaneously developed lupus anticoagulant antibodies during her second trimester of pregnancy. Although the recommended American Society of Reproductive Medicine (ASRM) diagnostic criteria for initiating a thrombophilia evaluation was not formally met, the patient's maintenance of low-molecular-weight heparin (LMWH) throughout her pregnancy may have contributed to the success of the pregnancy. When treating a patient with RPL, consideration of the comprehensive clinical picture should precede the need to strictly adhere to published criteria for using non-proven clinical interventions. A risk-benefit analysis ought to be considered when offering patients additional medications that may come with some risks but could significantly improve the chances of a successful clinical outcome, such as live birth. We aim to provide evidence to promote greater flexibility in guidelines so that a patient's unique autoimmune etiologies of RPL are not overlooked.

Benefits and risks of low molecular weight heparin use on reproductive outcomes: A retrospective cohort study

OBJECTIVE

Low molecular weight heparin (LMWH) has been given to reproductive-age women with various indications. This study aims to assess the benefits and risks of such use.

MATERIALS AND METHODS

We retrospectively reviewed data (n = 204) between Jan 2016 and May 2019. Logistic regression analysis was conducted to evaluate the correlation between indications and reproductive outcomes.

RESULTS

LMWH use had higher odds of live birth in women less than 30 years of age (OR: 4.98; 95% CI = 1.13-21.98; p = 0.034) and with protein S deficiency (OR: 3.90; 95% CI = 1.77-8.59; p = 0.001). For the subgroup of recurrent pregnant loss, LMWH use was only advantageous to women with protein S deficiency (OR: 2.45; 95%:1.01-5.97; p = 0.048). Risks such as preterm delivery, small-for-gestational-age, placental abruption, antepartum/postpartum hemorrhage were not significantly increased among subgroups. Women treated with LMWH and who had successful live births (n = 171) had a slightly increased risk of postpartum hemorrhage compared to controls (n = 8058) during this period in our institution (2.9% vs 1.2%, p < 0.001).

CONCLUSION

LMWH administration produces a higher chance of live-birth to women younger than 30 years of age or with protein S deficiency. However, risk of postpartum hemorrhage is increased.

Efficacy of Low Molecular Weight Heparin in Preventing Perinatal Venous Thrombosis: A Meta-Analysis

Background

There have been controversies about the preventive effect of low molecular weight heparin (LMWH) on venous thrombosis (VT) in the perinatal period. This study is aimed at exploring the effectiveness of LMWH in preventing perinatal VT through meta-analysis.

Methods

Databases such as CNKI, China Biology Medicine disc (CBMdisc), Wanfang, PubMed, MEDLINE, Embase, and Central were searched. Inclusion criteria were as follows: (1) subjects: women at high risk of perinatal VT; (2) experimental group and control group; (3) intervention measures: the experimental group was given LMWH, while the control group was given placebo or standard heparin or physical therapy; (4) outcomes: perinatal VT events or bleeding events; and (5) randomized controlled trials (RCTs). Jadad scale was used to evaluate the literature quality. The Mantel-Haenszel method was used to calculate the odds ratio (OR) and 95% confidence interval (CI). The chi-square test was used to analyze the heterogeneity of the included literature. Subgroup analysis was used to explore the source of heterogeneity. Publication bias was evaluated via funnel plot and Egger test.

Results

The incidence of perinatal VT in the LMWH group was lower than that in the control group (OR = 0.16, 95% CI (0.08, 0.32), P < 0.00001). There was no heterogeneity among literatures (P = 0.77, I² = 0%) and no publication bias. The incidence of postpartum VT in the LMWH group was lower than that in the control group (OR = 0.14, 95% CI (0.07, 0.30), P < 0.00001). There was no heterogeneity among literatures (P = 0.69, I² = 0%) and no publication bias. The incidence of perinatal bleeding in the LMWH group was higher than in the control group (OR = 1.72, 95% CI (1.06, 2.77), P = 0.03). There was no heterogeneity among literatures (P = 0.25, I² = 26%) and no publication bias.

Conclusion

LMWH can reduce the incidence of perinatal VT in high-risk women but increase the risk of bleeding. The use of LMWH to prevent perinatal VT should be closely monitored.

Cyclosporine A to Treat Unexplained Recurrent Spontaneous Abortions: A Prospective, Randomized, Double-Blind, Placebo-Controlled, Single-Center Trial

Background

The World Health Organization (WHO) has defined Unexplained Recurrent Spontaneous Abortion (URSA) as three and more consecutive miscarriages before the 20th week of gestation. To date, empiric therapy for patients with unexplained recurrent pregnancy loss (URPL) is not precise. Studies have shown that URSAs are associated with Th1/Th2 and Th17/Treg immune imbalances at the maternal-fetal interface. The immunosuppressant cyclosporine A (CsA) is widely used in patients with organ transplantation or autoimmune diseases, and it has a good safety profile in pregnant women. However, high-quality evidence for CsA treatment of URSAs is lacking. Our purpose with this study is to evaluate the efficacy and safety of CsA for improving pregnancy outcomes in patients with URSAs and to explore the role of CsA in regulating the immune balance.

Methods/Design

We expect to officially initiate our study at the Taizhou People's Hospital in March 2022. We defined the live birth rate as the primary outcome, and the secondary outcomes include the rates of successful pregnancy, miscarriage, pregnancy complications, and adverse pregnancy outcomes, and newborn birth weights. Patients who meet URSA eligibility criteria will be randomized in a 1:1 ratio into either a study group receiving CsA 2 weeks after fertilization or a control group receiving placebo at 2 weeks after fertilization (the women in both groups will receive the relevant treatment for 6 months). In addition, we will collect peripheral blood samples of the participants before and after the treatments, and we will isolate mononuclear cells and measure cytokine levels (IFN-γ, TNF-α, IL-2, IL-10, IL-6, IL-4) and Th1/Th2, Th17/Treg ratios.

Discussion

This is the first randomized controlled trial to evaluate the clinical and immunomodulatory effects of CsA on the pregnancy outcomes of women with URSA and our results will provide evidence to evaluate the use of CsA as a treatment for women with URSAs.