In which conditions is thromboprophylaxis (blood clot prevention) used postnatally in Malaysia?

Postnatal Thromboprophylaxis in Malaysia

In Malaysia, postnatal thromboprophylaxis is primarily guided by the Royal College of Obstetricians and Gynaecologists (RCOG) 2015 criteria, which recommends low-molecular-weight heparin (LMWH) for approximately 30% of all deliveries based on risk stratification into high-risk and intermediate-risk categories. 1

Risk Stratification Framework Used in Malaysia

Malaysian practice follows the RCOG risk assessment model, which categorizes women into three tiers 1:

High-Risk Patients (Require 6 weeks of LMWH)

• Any previous VTE 2
• Any woman requiring antenatal LMWH 2
• High-risk thrombophilia (antithrombin deficiency, homozygous Factor V Leiden or G20210A mutations, or compound heterozygous for both) 2
• Low-risk thrombophilia with family history of thrombosis 2

Intermediate-Risk Patients (Require at least 10 days of LMWH)

Any ONE of the following major factors: 2

• Cesarean delivery during labor
• BMI >40 kg/m²
• Postdelivery readmission
• Surgical procedures during puerperium
• Cancer
• Heart failure
• Active systemic lupus erythematosus
• Nephrotic syndrome
• Sickle cell disease
• Type 1 diabetes with nephropathy
• Inflammatory bowel disease
• Intravenous drug use

OR TWO or more of the following minor factors: 2

• Age >35 years
• Parity ≥3
• Obesity (BMI >30 kg/m²)
• Smoking
• Elective cesarean delivery
• Family history of VTE
• Low-risk thrombophilia
• Varicose veins
• Current systemic infection
• Preeclampsia
• Immobility
• Multiple pregnancy
• Preterm delivery
• Stillbirth
• Operative vaginal delivery
• Prolonged labor >24 hours
• Postpartum hemorrhage

Clinical Application in Malaysian Practice

Burden of Thromboprophylaxis

A 2018 Malaysian multicenter study demonstrated that 30.62% of all deliveries met criteria for postnatal thromboprophylaxis using the RCOG 2015 guidelines 1. The most common indication combinations were age, parity, BMI, cesarean section, and preterm births 1.

Vaginal Delivery Considerations

One in five women who deliver vaginally requires thromboprophylaxis in Malaysian practice when RCOG criteria are applied 1. This is substantially higher than other international guidelines would recommend 3.

Medication Choice and Acceptability

LMWH is the thromboprophylaxis of choice in more than two-thirds of Malaysian patients, despite the country having a sizable Muslim population 1. This high uptake rate demonstrates good acceptability of injectable prophylaxis even in religious contexts where concerns about animal-derived products might exist 1.

Practical Implementation Algorithm

Step 1: Universal Mechanical Prophylaxis

All women undergoing cesarean delivery should receive sequential compression devices starting preoperatively and continuing until fully ambulatory 2.

Step 2: Risk Assessment

Systematically evaluate for high-risk and intermediate-risk factors using the categories above 2, 1.

Step 3: Pharmacologic Prophylaxis Decision

For High-Risk Women:

• Initiate enoxaparin 40 mg subcutaneously once daily 2
• Continue for 6 weeks postpartum 2
• Combine with mechanical prophylaxis 2

For Intermediate-Risk Women:

• Initiate enoxaparin 40 mg subcutaneously once daily 2
• Continue for at least 10 days postpartum 2

For Low-Risk Women:

• Early mobilization and adequate hydration only 2
• No pharmacologic prophylaxis required 2

Step 4: Timing of Initiation

After neuraxial anesthesia: 2

• Prophylactic-dose enoxaparin (40 mg daily): Start 4 hours after catheter removal but not earlier than 12 hours after the block
• If significant intraoperative bleeding occurred: Consider unfractionated heparin initially due to shorter half-life and reversibility 2

Step 5: Special Populations

Class III Obesity (BMI ≥40 kg/m²):

• Use intermediate-dose enoxaparin 40 mg subcutaneously every 12 hours rather than once daily 2

Renal Dysfunction (creatinine clearance <30 mL/min):

• Switch to unfractionated heparin (5000-10,000 units subcutaneously every 8-12 hours) 2

Important Caveats

Risk-Benefit Considerations

The number needed to treat (NNT) to prevent one VTE episode in high-risk postpartum women ranges from 640 to 4000, while the number needed to harm (NNH) with wound complications may be as low as 200 2. This narrow therapeutic window emphasizes the importance of accurate risk stratification 2.

Comparison with Other Guidelines

The RCOG criteria used in Malaysia result in substantially higher prophylaxis rates compared to American College of Obstetricians and Gynecologists (ACOG) guidelines (85% vs 1% of cesarean deliveries) 3. The estimated VTE risk threshold for RCOG recommendations is approximately 0.12%, which is considerably lower than other international guidelines 4.

Monitoring and Complications

Watch for wound separation, wound hematomas, and bleeding complications, which occur more frequently with pharmacologic prophylaxis 2. The absolute VTE risk in the postpartum period without additional risk factors remains relatively low at approximately 0.07% 4.