Dystocia is a term used to describe the difficult delivery of a baby. In shoulder dystocia, the baby's head can be delivered, but the shoulders cannot pass through the birth canal. The shoulders are too wide to fit and become lodged behind the mother's pubic bone or the opening of the birth canal.
Typically, babies born with shoulder dystocia do not suffer long-term complications. If complications do occur, they are usually because the baby has become stuck too long in the birth canal.
For the baby:
- Lack of oxygen
- Broken arm or collarbone
- Arm nerve damage
For the mother:
- Tearing or bruising of the cervix, rectum, or vagina
- Bruising to the bladder
The baby's shoulder is lodged behind the mother's pubic bone.
Copyright © Nucleus Medical Media, Inc.
There are a variety of reasons why a baby's shoulders may become lodged during delivery. The most common reasons include:
Delivering very large babies with unusually high birth weights
Often caused by
or mothers who are very overweight
- Mother's pelvic opening being too small to allow the baby's shoulders to fit
Narrow Pelvic Opening
Copyright © Nucleus Medical Media, Inc.
The following factors increase the chance of a baby suffering from shoulder dystocia:
- Mothers who are diabetic
- Mothers who are significantly overweight
- Mothers of small stature may also have a small pelvic structure
- A baby who is very large
The signs of shoulder dystocia are noticeable when the baby's head is delivered. The delivery does not progress because the baby's shoulders are lodged in the birth canal behind the mother's pubic bone.
Shoulder dystocia cannot be diagnosed until it occurs during delivery. It can sometimes be predicted by determining the weight and size of the fetus and the structure of the mother's pelvis. This information can help determine whether a vaginal delivery is safe for the mother and baby. An
may be done prior to labor to determine if the baby is too large to fit safely through the birth canal during delivery.
After shoulder dystocia is diagnosed, your doctor will go through a series of maneuvers to attempt to dislodge the baby's shoulder and allow for a vaginal delivery. Options include:
- Manipulated vaginal delivery—There are a variety of maneuvers that the doctor can do to help the mother deliver the baby vaginally.
- Cesarean delivery
(C-section)—If the maneuvers do not work, the baby will need to be delivered via an emergency C-section. For babies who are at risk of shoulder dystocia because of their large size, a C-section may be scheduled.
Shoulder dystocia cannot be prevented. Babies who are at risk of shoulder dystocia because of large size can be evaluated prior to delivery with regular prenatal care and ultrasound testing. Women with diabetes or who are very overweight should have the size of their babies estimated. Women with pregnancies complicated by macrosomia are at risk for shoulder dystocia and should be counseled about the option of delivery by C-section.
American College of Obstetricians and Gynecologists. Shoulder dystocia. American College of Obstetricians and Gynecologists.
Practice Bulletin No. 40.
Cesarean section. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed/what.php. Updated September 2, 2013. Accessed September 5, 2013.
American College of Obstetricians and Gynecologists. Fetal Macrosomia.
ACOG Practice Bulletin No.22. Accessed December 17, 2012.
World Health Organization.
Managing complications in pregnancy and childbirth: a guide for midwives and doctors. World Health Organization website.
Accessed September 5, 2013.
Last reviewed September 2013 by Andrea Chisholm, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © EBSCO Publishing. All rights reserved.