Health Library

Shoulder Dystocia

Definition

Shoulder dystocia is when the baby's shoulders become stuck during birth. This is an emergency that can cause serious problems.

Most babies will be born safely with some help. Sometimes the baby may be stuck in the birth canal too long. That can cause problems for the baby, such as:

  • Lack of oxygen
  • Broken arm or collarbone
  • Arm nerve damage
  • Paralysis

It can also cause problems for the mother, such as:

  • Tearing or bruising of the cervix, rectum, or vagina
  • Bruising to the bladder
  • Severe bleeding
Shoulder Dystocia
Shoulder Dystocia
The baby's shoulder is lodged behind the mother's pubic bone.
Copyright © Nucleus Medical Media, Inc.

Causes

Shoulder dystocia is caused by:

  • Baby’s shoulders are too wide—larger babies are common in women with diabetes or late-term pregnancies
  • The pelvic opening is too small for child

One or both could happen during labor.

Narrow Pelvic Opening
Pelvis birth
Copyright © Nucleus Medical Media, Inc.

Risk Factors

Things that may increase a baby's chance of shoulder dystocia include:

  • Mother has diabetes
  • Mother is significantly overweight
  • Mother has small stature which may mean small pelvis
  • A very large baby
  • Shoulder dystocia in previous birth

Signs and Symptoms

There are no symptoms of shoulder dystocia.

Diagnosis

The doctor or midwife will know when the birth process stops after the head is born.

Prenatal tests will estimate the size of the fetus and the pelvis. These tests may show a risk for shoulder dystocia.

An ultrasound may be done before labor. The doctor will be able to see if the baby is too large to fit safely through the birth canal. A vaginal delivery may not be a safe method if the baby is too large.

Treatment

The goal of treatment is to get the baby unstuck as fast as possible. This will allow the vaginal birth to continue. The doctor or midwife may:

  • Reposition the mother
  • Reposition the baby to try to move the shoulder away from the bone

A C-section may be needed if the baby remains stuck in the birth canal.

Prevention

Shoulder dystocia cannot always be prevented. If you have a high risk of shoulder dystocia the doctor may offer:

  • Early induced labor—the baby will be smaller
  • Planned C-section

Resources

American Congress of Obstetricians and Gynecologists
http://www.acog.org

American Pregnancy Association
http://www.americanpregnancy.org

Canadian Resources

Pregnancy Info—The Society of Obstetricians and Gynaecologists of Canada
http://www.pregnancyinfo.ca

Women's Health Matters
http://www.womenshealthmatters.ca

References

Menticoglou, S. Shoulder dystocia: incidence, mechanisms, and management strategies. Int J Womens Health, 2018; 10: 723-732.

Shoulder dystocia. EBSCO DynaMed website. Available at:https://www.dynamed.com/condition/shoulder-dystocia . Accessed March 21, 2022.

World Health Organization. Managing complications in pregnancy and childbirth: a guide for midwives and doctors. World Health Organization website. Available at: http://whqlibdoc.who.int/publications/2007/9241545879%5Feng.pdf. Accessed March 21, 2022.