Shoulder dystocia will often lead to a 3rd degree tear. If a birth has been complicated by shoulder dystocia, medical practitioners must be sure to check the perineum and anal sphincter for signs of damage.
Shoulder dystocia is a complication of a vaginal delivery. It is when the baby’s shoulder becomes stuck behind the mother’s pubic bone during the birth. Shoulder dystocia can happen to anyone having a vaginal delivery, although there are certain factors that increase the risk, including:
- Maternal diabetes
- Larger than average baby
- Maternal obesity
- Induction of labour
- Prolonged labour
If shoulder dystocia does occur, medical practitioners must be quick to act or the baby could be severely injured.
Indeed, the head will have been delivered so the baby will be able to inhale. However, the chest will not be able to expand during an intake of breathe. Consequently the baby will be deprived of oxygen. If this continues for too long, the baby will suffer brain damage.
Therefore no time should be wasted in managing shoulder dystocia. The mother should be asked to stop pushing and a senior obstetrician called for. A medical manoeuvre should then be attempted, whereby pressure is placed on the abdomen. If this does not work, other manoeuvres should be tried. Alternatively doctors may choose to proceed with an emergency caesarean section.
Shoulder dystocia and 3rd degree tears
Shoulder dystocia is thought to occur in one in 150 births. Medical practitioners are well-trained in the manoeuvres required to release the shoulders and it is rare that a baby will suffer brain damage. Around 10% of babies will experience brachial plexus injury, but this will normally resolve and only 1% of babies will have long-term nerve damage.
However, it is likely that the mother will experience a 3rd or 4th degree tear. This is when the perineum tears down to the anus. Such tears are commonly associated with shoulder dystocia because the manoeuvres needed to release the shoulders put the perineum under considerable strain. Sometimes the perineum will not be able to stretch far enough and will tear.
Additionally, medical practitioners may need to use forceps and/or perform an episiotomy. Both will increase the risk of a 3rd degree tear occurring.
Repairing a 3rd degree tear
When a birth is complicated by shoulder dystocia, medical practitioners should be aware of the fact that the mother may have sustained a 3rd degree tear. A thorough examination should then be carried out to check whether there is an injury present. If so, a repair should be conducted in theatre.
If clinicians fail to diagnose a 3rd degree tear which has been caused by shoulder dystocia, there may be a case of medical negligence. Contact us to find out more.