Asphyxia at birth, often called birth asphyxia or neonatal asphyxia, occurs when a newborn baby does not get enough oxygen before, during, or immediately after delivery. This lack of oxygen can cause serious damage to the baby’s brain and other organs, sometimes leading to long-term disabilities or even death. Understanding what causes asphyxia at birth involves looking at various factors that interfere with the baby’s oxygen supply during the critical moments surrounding birth.
One of the most common causes is **problems with the umbilical cord**, which is the lifeline between the baby and the placenta. The umbilical cord can become compressed, knotted, or prolapsed (where it slips into the birth canal ahead of the baby), all of which can reduce or completely block the flow of oxygen-rich blood to the baby. When the cord is compressed, it acts like a kinked hose, limiting oxygen delivery and causing the baby to become deprived of oxygen.
Another major cause involves **issues with the placenta**, the organ that provides oxygen and nutrients to the baby during pregnancy. Conditions such as placental abruption, where the placenta detaches prematurely from the uterus, or placenta previa, where the placenta covers the cervix, can severely reduce oxygen supply. If the placenta cannot function properly, the baby may not receive enough oxygen, leading to asphyxia.
**Maternal health problems** also play a significant role. High or low blood pressure in the mother, including conditions like preeclampsia or eclampsia, can affect blood flow to the placenta and thus to the baby. Additionally, maternal hypotension (low blood pressure), often caused by anesthesia or certain medications during labor, can reduce the oxygen supply to the fetus.
**Premature birth** increases the risk because premature babies often have underdeveloped lungs and may struggle to breathe effectively on their own immediately after birth. This immaturity can contribute to insufficient oxygen levels.
Sometimes, **uterine hyperstimulation** caused by labor-inducing drugs like Pitocin or Cytotec can lead to overly frequent or intense contractions. These contractions can reduce blood flow through the placenta, limiting oxygen delivery to the baby.
Other factors include **ruptured uterus**, where the uterus tears during labor, and **fetal stroke**, which can disrupt blood flow within the baby’s brain. Low amniotic fluid (oligohydramnios) can also contribute by limiting the cushioning and protection around the baby, increasing the risk of cord compression.
Medical errors or delays during labor and delivery can worsen or cause asphyxia. For example, failure to recognize signs of fetal distress—such as abnormal heart rate patterns or decreased movement—or delays in performing an emergency cesarean section can prolong the period the baby is deprived of oxygen. Inadequate resuscitation efforts immediately after birth can also contribute to the severity of asphyxia.
The consequences of asphyxia depend on how long and how severely the baby is deprived of oxygen. Even a brief period without enough oxygen can cause brain injury, leading to conditions like cerebral palsy, epilepsy, developmental delays, and problems with motor skills, speech, and behavior. More prolonged oxygen deprivation can result in severe brain damage or death.
In summary, birth asphyxia is caused by any event or condition that disrupts the baby’s oxygen supply before, during, or right after birth. These include umbilical cord complications, placental problems, maternal health issues, premature birth, uterine hyperstimulation, and sometimes medical errors. Preventing asphyxia requires careful monitoring of both mother and baby throughout pregnancy and labor, prompt recognition of distress signals, and immediate, effective medical intervention when problems arise.
