Facial nerve palsy due to birth trauma is the loss of controllable (voluntary) muscle movement in an infant's face due to pressure on the facial nerve in the face just before or at the time of birth.
An infant's facial nerve is also called the seventh cranial nerve. It can be damaged just before or at the time of delivery.
Most of the time the cause is unknown. But a difficult delivery, with or without the use of an instrument called forceps, may lead to this condition.
Some factors that can cause birth trauma (injury) include:
Most of the time, these factors do not lead to facial nerve palsy or birth trauma.
The most common form of facial nerve palsy due to birth trauma involves only the lower part of the facial nerve. This part controls the muscles around the lips. The muscle weakness is mainly noticeable when the infant cries.
The newborn infant may have the following symptoms:
A physical exam is usually all that is needed to diagnose this condition. In rare cases, a nerve conduction test is needed. This test can pinpoint the exact location of the nerve injury.
Brain imaging tests are not needed unless your health care provider thinks there is another problem (such as a tumor or stroke).
In most cases, the infant will be closely monitored to see if the paralysis goes away on its own.
If the baby's eye does not close all the way, an eyepad and eyedrops will be used to protect the eye.
Surgery may be needed to relieve pressure on the nerve.
Infants with permanent paralysis need special therapy.
The condition usually goes away on its own in a few months.
In some cases, the muscles on the affected side of the face become permanently paralyzed.
The provider will usually diagnose this condition while the infant is in the hospital. Mild cases involving just the lower lip may not be noticed at birth. A parent, grandparent, or other person may notice the problem later.
If the movement of your infant's mouth looks different on each side when they cry, you should make an appointment with your child's provider.
There is no guaranteed way to prevent pressure injuries in the unborn child. The proper use of forceps and improved childbirth methods have reduced the rate of facial nerve palsy.
Reviewed By: Amit M. Shelat, DO, FACP, Attending Neurologist and Assistant Professor of Clinical Neurology, SUNY Stony Brook, School of Medicine, Stony Brook, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.