Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Birth Asphyxia

(Perinatal Asphyxia)

By

Arcangela Lattari Balest

, MD, University of Pittsburgh, School of Medicine

Reviewed/Revised Jan 2024
VIEW PROFESSIONAL VERSION
Topic Resources

Birth asphyxia is a decrease in blood flow to a newborn's tissues or a decrease in oxygen in a newborn's blood before, during, or just after delivery.

When a baby is born, the doctor or midwife examines the newborn for any obvious abnormalities or signs of distress. The newborn's condition immediately after birth is recorded at 1 minute and at 5 minutes after birth using the Apgar score. The Apgar score is used to assign points for heart rate, effort to breathe, muscle tone, reflexes, and color. A score of 7 to 10 is considered normal, 4 to 6 is intermediate, and 0 to 3 is low. A low Apgar score is a sign that the newborn is having difficulty and may need extra assistance with breathing or blood circulation. The Apgar score does not predict anything about the baby's health after the first few minutes of life.

Table

Apgar Score

Characteristic

Acronym*

Score†

0

1

2

Color of skin

Appearance

All blue, pale

Pink body, blue hands and feet

All pink

Heart rate

Pulse

No pulse

Less than 100 beats per minute

More than 100 beats per minute

Reflex response to stimulation of the nose (by touching it with a finger or a catheter)

Grimace

No response to stimulation

Grimace

Sneeze, cough

Muscle tone

Activity

Limp, no movement

Some bending of arms and legs

Active movement

Breathing

Respiration

No breathing

Irregular, slow

Good cry

* The word "Apgar" is also an acronym. The letters A, P, G, A, and R correspond to the bold letters in this column.

† The baby is given a score from 0 to 2 for each of 5 characteristics. A total score of 7 to 10 at 5 minutes is considered normal, 4 to 6 is intermediate, and 0 to 3 is low.

Babies with a low Apgar score may be having trouble with breathing or blood flow. Birth asphyxia (also called perinatal asphyxia) is a decrease in blood flow to the newborn's tissues or a decrease in oxygen in the newborn's blood before, during, or just after delivery. Some potential causes include the following:

Sometimes the exact cause of birth asphyxia cannot be identified.

Regardless of the cause, affected newborns appear pale and lifeless at birth. They breathe weakly or not at all and have a very slow heart rate. The doctors and nurses provide care to revive (resuscitate) the newborn. Resuscitation may include use of a resuscitation bag and mask to push air into the lungs or insertion of a breathing tube in the newborn's throat (endotracheal intubation). If asphyxia resulted from rapid blood loss, the newborn may be in shock Shock Shock is a life-threatening condition in which blood flow to the organs is low, decreasing delivery of oxygen and thus causing organ damage and sometimes death. Blood pressure is usually low... read more . They are immediately given fluids by vein, and sometimes a blood transfusion Overview of Blood Transfusion A blood transfusion is the transfer of blood or a blood component from one healthy person (a donor) to a sick person (a recipient). Transfusions are given to increase the blood's ability to... read more Overview of Blood Transfusion or plasma.

Newborns with asphyxia may show signs of injury to one or more organ systems, including the following:

  • Heart: Poor color, low blood pressure

  • Lungs: Difficulty breathing and low oxygen levels

  • Brain: Lethargy, seizures, or even coma

  • Kidneys: Reduced output of urine

  • Liver: Difficulty making proteins that are needed for blood to clot normally

  • Intestines: Difficulty digesting milk

  • Blood forming system: Low platelet count and bleeding

Most of the organs damaged by birth asphyxia recover over a week, but brain damage may persist in some infants. Infants who have no or minimal injury to the brain may have no ongoing health problems. Those who have moderate to severe injury to the brain may have permanent developmental issues, ranging from mild learning disorders Learning Disorders Learning disorders involve an inability to acquire, retain, or broadly use specific skills or information, resulting from deficiencies in attention, memory, or reasoning and affecting academic... read more to delayed development to cerebral palsy Cerebral Palsy (CP) Cerebral palsy refers to a group of conditions that involve difficulty moving and muscle stiffness (spasticity). It results from brain malformations that occur before birth as the brain is developing... read more . Some infants with severe asphyxia infants do not survive.

NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
VIEW PROFESSIONAL VERSION
quiz link

Test your knowledge

Take a Quiz!
iOS ANDROID
iOS ANDROID
iOS ANDROID
TOP