Why is delayed cord clamping beneficial, and when should it be avoided?

Delayed cord clamping (e.g. >1 minute) allows a placental transfusion to the baby, increasing the neonatal blood volume and iron stores - reducing neonatal and infant iron deficiency anaemia.

It should be avoided if the baby needs immediate resuscitation (born in poor condition), if the mother is bleeding, or if the mother is Rhesus isoimmunised.

Clinical relevance. Delayed cord clamping reduces neonatal anaemia and supports the transition, with specific exceptions (resuscitation, bleeding, Rhesus).

More Detail

Delayed cord clamping

Timing of cord clamping affects the neonatal blood volume and iron stores.

Benefits of delayed clamping

• Allows a placental transfusion (extra blood from the placenta to the baby).
• Increases neonatal blood volume and iron stores, reducing neonatal and infant iron deficiency anaemia.
• This is the default policy in most births (e.g. wait at least 1 minute or until the cord stops pulsating).

When to avoid (clamp early)

• The baby is born in poor condition and needs immediate resuscitation.
• The mother is bleeding (e.g. needs active third-stage management).
• The mother is Rhesus isoimmunised (limit transfer of affected/antibody-laden placental blood and allow prompt neonatal assessment).

Relevance to the transition

• Delayed clamping supports a smoother circulatory transition by maintaining blood volume (avoiding hypovolaemia, a PPHN trigger).