How does applying controlled traction to the umbilical cord after placental separation aid placental delivery and reduce postpartum hemorrhage?

How Controlled Cord Traction Helps in Placental Delivery

Controlled cord traction is a key component of active management of the third stage of labor that significantly reduces postpartum hemorrhage (relative risk 0.38), decreases blood loss by approximately 79 mL, and reduces the need for manual placental removal, without increasing maternal complications. 1

Mechanism and Benefits

Controlled cord traction works as part of a comprehensive active management strategy that fundamentally changes the physiology of the third stage of labor:

Primary Effects on Maternal Outcomes

Active management (which includes controlled cord traction, prophylactic uterotonics, and early cord clamping in traditional protocols) reduces:

• Postpartum hemorrhage risk by 62% (RR 0.38,95% CI 0.32-0.46) across 6,284 participants 1
• Mean blood loss by 79 mL (95% CI -94 to -64) 1
• Retained placenta requiring manual removal from 6.1% to 4.2% (RR 0.69) 2
• Duration of third stage >15 minutes from 14.3% to 4.5% (RR 0.31) 2

The technique also reduces maternal discomfort and pain during placental delivery 2.

How It Works Physiologically

The controlled traction technique (Brandt-Andrews method) applies gentle, steady traction on the umbilical cord while providing counter-traction on the uterus above the pubic symphysis. This:

1. Facilitates complete placental separation by applying mechanical force that complements uterine contractions induced by oxytocin
2. Shortens the third stage duration, reducing the window for excessive bleeding
3. Prevents incomplete placental separation that leads to retained fragments and continued bleeding
4. Allows earlier identification of abnormal placentation requiring manual intervention

Modern Evidence-Based Protocol

The contemporary approach has evolved from traditional active management:

Timing Sequence (Resource-Poor Settings Guideline)

1. Administer oxytocin 5-10 IU (IM or slow IV) immediately after delivery of the infant 1
2. Allow delayed cord clamping for 3 minutes to complete placental transfusion to the infant 1
3. After cord clamping, proceed with controlled cord traction to deliver the placenta 1

This sequence is critical: the uterotonic administration hastens placental transfusion while simultaneously promoting uterine contraction. After approximately 3 minutes, placental transfusion is complete, and controlled cord traction can safely commence without compromising neonatal blood volume 1.

Important Nuance: Modern Guidelines Have Changed

The International Confederation of Midwives and International Federation of Gynaecologists and Obstetricians removed immediate cord clamping from their active management recommendations 1. This means controlled cord traction should be performed after delayed cord clamping, not immediately after birth as in older protocols.

Clinical Application Algorithm

For vaginal delivery:

1. Give oxytocin 5-10 IU at delivery of anterior shoulder or immediately postpartum
2. Wait 3 minutes for placental transfusion (infant on mother's abdomen or lower)
3. Clamp and cut cord
4. Apply controlled cord traction using Brandt-Andrews technique
5. Await signs of placental separation (uterine contraction, cord lengthening, gush of blood)
6. Apply steady traction with counter-pressure above pubic symphysis
7. Deliver placenta with maternal effort if needed

For cesarean section: The evidence shows cord traction is superior to manual removal at CS, with less endometritis (RR 1.64 for manual removal), less blood loss (94 mL less), and shorter hospital stay 3. However, one recent trial found no clinically significant difference when both techniques were compared in modern practice 4.

Critical Caveats and Pitfalls

What NOT to Do

• Do not perform manual removal routinely to prevent PPH outside specialized settings—reserve this for severe, uncontrollable hemorrhage 5
• Do not apply excessive traction before signs of placental separation, as this risks uterine inversion (though no cases occurred in the 4,013 women studied in the TRACOR trial) 2
• Do not skip the uterotonic—oxytocin is the mainstay of active management; cord traction alone is insufficient 1

Context-Dependent Considerations

In high-resource settings: The TRACOR trial (2013) found that when prophylactic oxytocin is given universally, adding controlled cord traction did not significantly reduce PPH incidence (9.8% vs 10.3%, RR 0.95) 2. This suggests that in settings with reliable oxytocin administration, the incremental benefit of cord traction may be primarily in reducing retained placenta and shortening third stage duration rather than preventing hemorrhage.

In low-resource settings: Where oxytocin availability may be limited or storage conditions suboptimal, controlled cord traction becomes more critical as part of the complete active management package 1.

Comparison with Expectant Management

Expectant management (hands-off, awaiting spontaneous delivery) results in:

• 2.6-fold higher PPH risk
• More retained placentas (4.5% vs 1.6% with controlled traction) 6
• Greater need for additional uterotonics (5.1% vs 2.3%) 6

Active management is definitively superior for maternal outcomes 1.

Additional Hemorrhage Prevention Measures

When controlled cord traction is used, consider adding:

• Tranexamic acid 1g IV within 3 hours of birth if PPH occurs (reduces mortality from hemorrhage) 5
• Uterine massage after placental delivery to maintain contraction 7
• Careful inspection for retained fragments or genital tract trauma

The combination of oxytocin administration, delayed cord clamping for neonatal benefit, followed by controlled cord traction represents the current evidence-based standard that balances maternal safety with neonatal outcomes 1.