Understanding Shoulder Dystocia: Causes, Prevention, and Impact on Babies

Introduction

Shoulder dystocia is a medical complication that occurs during childbirth when a baby's head passes through the birth canal, but the shoulders get stuck behind the mother's pelvic bone. This condition poses potential risks for both the mother and the baby, which is why understanding its causes, prevention measures, and potential consequences is crucial for parents and healthcare professionals. In this article, we look at the impact of shoulder dystocia; exploring what it is, how it happens, ways to prevent it, its symptoms, and the risks it poses for new babies. 

What is Shoulder Dystocia?

Shoulder dystocia is a childbirth complication characterised by the difficulty of delivering a baby's shoulders after the head has passed through the birth canal. It happens when one or both of the baby's shoulders become stuck behind the mother's pelvic bone. This can lead to a delay in the completion of childbirth, increasing the risk of complications for both the mother and the baby. 

How Does Shoulder Dystocia Happen? 

Several factors contribute to the occurrence of shoulder dystocia, including foetal, maternal, and obstetric factors.  

Foetal factors may involve a larger-than-average baby size, often referred to as macrosomia. This occurs due to the fact the baby may be too large for vaginal delivery, causing them to get stuck behind the mother’s pelvic bone. Research suggests that foetal macrosomia is the largest risk factor for babies suffering shoulder dystocia. 

Maternal factors include gestational diabetes, obesity, or a history of shoulder dystocia in previous pregnancies.  

If a mother has gestational diabetes, the risk level of shoulder dystocia increases. This is because it is more likely that babies born of diabetic mothers have wider shoulders, chests, and abdominal circumference than babies who have non-diabetic mothers. Therefore, increasing their likelihood of becoming stuck during delivery. 

Obesity increases the risk of shoulder dystocia during childbirth, due to a combination of maternal and foetal factors associated with excess body weight. Here are several reasons why obesity is considered a risk factor for shoulder dystocia: 

• Obesity increases the chances of gestational diabetes and foetal macrosomia 

• Obesity can alter the shape of the maternal pelvis, causing difficulty for the baby to navigate the birth canal 

• Excess fat tissue in the abdominal area can impede the progress of the baby during delivery 

• Obesity is associated with changes in hormones and can affect maternal metabolism, which can influence foetal growth and development 

Research has also shown that if a mother has suffered shoulder dystocia issues in previous pregnancies, the risk of a reoccurrence increases significantly. It is thought that 10-20% of women have the same complication in the subsequent birth. 

Obstetric factors include the use of certain birthing positions, such as the lithotomy position (lying flat on your back). This position can prevent the sacrum from moving during birth, which narrows the room in the mother’s pelvis for the baby’s shoulders to fit through. 

Improper use of birthing tools such as forceps being used with excess force can result in the baby being pulled forcibly, causing damage to their shoulder. 

During childbirth, if the baby's head passes through the birth canal while the shoulders remain lodged, it can result in compression of the umbilical cord, reducing oxygen flow to the baby. Additionally, the prolonged pressure on the baby's head and neck can lead to injuries such as brachial plexus injuries and fractures. 

How Can Shoulder Dystocia Be Prevented? 

Preventing shoulder dystocia involves identifying and managing risk factors during pregnancy and labour. Regular prenatal check-ups are essential for monitoring the baby's growth and identifying any potential issues, such as macrosomia. Mothers with gestational diabetes should actively manage their blood sugar levels to reduce the risk of delivering a larger-than-average baby. 

During labour, healthcare professionals can adopt certain techniques to minimise the risk of shoulder dystocia. These may include changing the mother's birthing position, avoiding the use of excessive force, and employing manoeuvres to dislodge the baby's shoulders safely. 

What Are the Symptoms of Shoulder Dystocia? 

Recognising the symptoms of shoulder dystocia is crucial for prompt intervention. Some common signs include: 

• Difficulty delivering the baby's shoulders after the head has emerged 

• A delayed delivery of the baby's body 

• The need for additional assistance, such as forceps or vacuum extraction, to complete the birth 

Healthcare professionals are trained to identify these signs and take immediate action to address the situation. 

How Does Shoulder Dystocia Impact a New Baby? 

Shoulder dystocia can have various consequences, both immediate and long-term. In the short term, it may lead to birth injuries such as brachial plexus injuries, which affect the nerves controlling the arm and hand. Fractures, particularly to the baby's clavicle or arm bones, can also occur. In severe cases, oxygen deprivation during prolonged shoulder dystocia can lead to hypoxic-ischemic encephalopathy, a condition that affects the baby's brain function. 

Long-term consequences may include developmental delays, physical disabilities such as cerebral palsy and Erb’s palsy, and the need for ongoing medical interventions. However, it is important to note that not all babies who experience shoulder dystocia will face long-term complications, and outcomes vary depending on the severity of the case and the timeliness of interventions. 

Shoulder dystocia can have significant physical and emotional impacts on mothers. The prolonged and intense efforts to resolve shoulder dystocia can lead to increased maternal discomfort, potential injuries, and a heightened risk of postpartum complications. Mothers who experience shoulder dystocia may face a longer recovery period, both physically and emotionally, as they grapple with the unexpected challenges of childbirth. Furthermore, the experience may contribute to feelings of anxiety or distress related to the well-being of the newborn. 

What to Do if You Think Your Child Has Shoulder Dystocia? 

If you suspect that your child may have experienced shoulder dystocia during birth, it is essential to seek medical attention promptly. Healthcare professionals can assess the baby's condition, perform necessary diagnostic tests, and initiate appropriate interventions to address any complications. Early detection and intervention can significantly improve outcomes for both the mother and the baby. 

Conclusion 

Shoulder dystocia is a challenging complication that can arise during childbirth, posing risks to both mothers and babies. Understanding the causes, prevention measures, symptoms, and potential consequences of shoulder dystocia is crucial for immediate interventions. By addressing risk factors early in pregnancy, adopting appropriate labour management techniques, recognising, and responding promptly to signs of shoulder dystocia, healthcare professionals can enhance the likelihood of a safe and healthy delivery for both mother and baby. If you have concerns about shoulder dystocia, it is important to discuss them with your healthcare provider to ensure a comprehensive and individualised approach to your pregnancy and childbirth experience.