PT/INR Testing After LSCS: Not a Routine Requirement
PT/INR testing is NOT routinely indicated after Lower Segment Caesarean Section (LSCS) in standard clinical practice. This test is only performed when specific clinical indications exist, such as monitoring therapeutic anticoagulation or evaluating unexplained bleeding complications.
Why PT/INR is NOT Standard Post-LSCS Care
The major international guidelines on post-cesarean thromboprophylaxis make no mention of routine PT/INR monitoring because:
- Standard thromboprophylaxis uses LMWH, which does not require PT/INR monitoring 1
- The American College of Chest Physicians recommends prophylactic LMWH for high-risk patients without any coagulation testing requirements 1
- The Society for Maternal-Fetal Medicine guidelines emphasize mechanical and pharmacologic prophylaxis but do not include routine coagulation monitoring 1
When PT/INR Testing IS Indicated Post-LSCS
PT/INR should only be checked in these specific scenarios:
Therapeutic Anticoagulation Management
- Women on warfarin therapy who require monitoring of anticoagulation intensity 1
- Patients with acute VTE during pregnancy transitioning from LMWH to warfarin postpartum (after at least 5 days when warfarin is safe for breastfeeding) 1
Bleeding Complications
- Unexplained or excessive postpartum hemorrhage requiring investigation of coagulopathy 1
- Suspected disseminated intravascular coagulation or other acquired coagulopathies 1
Pre-existing Coagulation Disorders
- Known liver disease affecting synthetic function
- Suspected vitamin K deficiency
- Monitoring patients with known factor deficiencies
Standard Post-LSCS Thromboprophylaxis Approach
All women undergoing cesarean delivery should receive sequential compression devices starting before surgery and continuing until fully ambulatory 1. This requires no laboratory monitoring.
For pharmacologic prophylaxis:
- Low-molecular-weight heparin is the preferred agent and does not require PT/INR monitoring 1
- Women with previous VTE or thrombophilia should receive both mechanical and pharmacologic prophylaxis for 6 weeks postoperatively 1
- Women with one major risk factor or two minor risk factors should receive prophylactic LMWH while hospitalized 1
- LMWH monitoring uses anti-Xa levels if needed, not PT/INR 1
Common Clinical Pitfall
The most common reason for inappropriate PT/INR ordering post-LSCS is confusion about anticoagulation monitoring. Healthcare providers may mistakenly believe that all anticoagulation requires PT/INR monitoring, when in fact:
- LMWH does not affect PT/INR significantly 1
- Prophylactic doses of LMWH rarely require any laboratory monitoring 1
- Only warfarin therapy requires PT/INR monitoring, which is typically avoided in the immediate postpartum period due to breastfeeding considerations 1
Risk Assessment Without Laboratory Testing
Risk stratification for VTE prophylaxis is based on clinical factors, not laboratory values 1:
Major risk factors include: previous VTE, thrombophilia, immobility ≥1 week antepartum, postpartum hemorrhage with surgery, preeclampsia with fetal growth restriction 1
Minor risk factors include: obesity, multiple pregnancy, smoking, age >35 years, prolonged labor >24 hours 1
No routine coagulation testing is required for this risk assessment 1.