What Causes Birth Injuries During Labor and Delivery

Every year, thousands of families face the unexpected reality of a birth injury. Understanding what causes these injuries is an essential first step in processing what happened, advocating for proper care, and making informed decisions about treatment and support.

Birth injuries do not happen for a single, simple reason. They result from complex interactions between fetal factors, maternal health conditions, labor complications, and sometimes the medical interventions meant to help. This article breaks down the causes of birth injuries in clear, practical terms so you can understand the medical information behind these life-changing events.

What Counts as a Birth Injury and How They Differ from Birth Defects

A birth injury is physical harm that occurs to a baby during the labor and delivery process or immediately after. These range from minor, temporary issues like small bruises or swelling to serious, permanent conditions affecting the brain, nerves, or bones.

The medical community distinguishes between birth injuries (trauma that occurs during the birth process) and birth defects (conditions that develop during pregnancy). This distinction matters because it helps identify what went wrong and when.

Some birth injuries heal completely within weeks. Others require years of therapy, medical intervention, or lifelong care. The severity depends on which body systems were affected, how quickly the injury was recognized, how effectively it was treated, and what treatment was available.

Why Larger Babies Suffer Higher Risks

Macrosomia, the medical term for a baby weighing more than 9 pounds at birth, significantly increases injury risk. Larger babies have more difficulty moving through the birth canal, which can lead to:

• Shoulder dystocia, where the baby’s shoulder gets stuck behind the mother’s pelvic bone after the head emerges. This emergency situation can cause brachial plexus injuries affecting the nerves that control arm movement.
• Extended labor that exhausts both mother and baby, potentially leading to oxygen deprivation.
• Higher likelihood of requiring forceps or vacuum extraction, which carry their own risks.

Healthcare providers typically monitor fetal weight estimates throughout pregnancy using ultrasound measurements. When macrosomia is suspected, doctors should discuss delivery options, though ultrasound predictions aren’t always accurate.

Birth Complications Caused by Large Head Size (Macrocephaly)

Macrocephaly means an unusually large head circumference. Since the head is typically the largest part of the baby passing through the birth canal, an increase in size creates mechanical challenges.

Babies with macrocephaly face increased risk of cephalopelvic disproportion, where the head simply doesn’t fit through the mother’s pelvis. This can result in:

• Prolonged pushing stages that reduce oxygen supply to the baby.
• Increased need for operative delivery with instruments.
• Greater pressure on the skull, potentially causing fractures or intracranial bleeding.

Sometimes macrocephaly indicates an underlying condition like hydrocephalus (fluid accumulation in the brain). Other times it’s simply a variation of normal, especially in families with larger head sizes. Either way, it requires careful monitoring during delivery.

How Premature Birth Increases the Risk of Birth Injuries

Premature babies, especially those born before 32 weeks or weighing less than 3.3 pounds, have bodies that aren’t fully prepared for the stress of birth. Their risks include:

• Underdeveloped lungs that can’t efficiently exchange oxygen, leading to respiratory distress and potential brain injury from oxygen deprivation.
• Extremely fragile blood vessels in the brain that can bleed with even normal birth pressures, causing intraventricular hemorrhage.
• Weaker bones that fracture more easily.
• Immature immune systems that can’t fight off infections effectively.

The medical team’s challenge with premature deliveries is balancing the risks of staying in the womb (if there are complications threatening the mother or baby) against the risks of being born too early. Sometimes birth injury occurs because premature delivery was the safest option available, even though it carries inherent risks.

How Breech and Abnormal Baby Positions Cause Birth Injuries

The safest position for birth is head-down, face toward the mother’s back. Any other position increases injury risk:

• Breech position (bottom or feet first) puts stress on the head and neck as they come through last, when the birth canal hasn’t been fully stretched by a larger part. This also increases risk of umbilical cord compression.
• Face or brow presentation means the baby’s face or forehead comes first instead of the crown of the head, requiring more space to navigate the pelvis.
• Transverse lie (baby positioned sideways) makes vaginal delivery impossible without repositioning or cesarean section.

Most providers recommend cesarean delivery for breech babies at term because of these risks. However, if labor progresses quickly or position isn’t detected early, vaginal breech delivery may occur, carrying higher injury rates.

How Low Amniotic Fluid (Oligohydramnios) Can Lead to Birth Injuries

Oligohydramnios, or low amniotic fluid, removes the baby’s protective cushioning. Amniotic fluid serves several critical functions: it protects against compression, allows movement for proper musculoskeletal development, and provides space for the umbilical cord to float freely.

When fluid levels drop too low, risks include:

• Umbilical cord compression during contractions, cutting off oxygen supply intermittently or continuously.
• Increased pressure on the baby’s body during labor.
• Poor tolerance of labor stress, leading to fetal distress.

Oligohydramnios can result from ruptured membranes, placental problems, or certain fetal conditions. It requires close monitoring and often prompts earlier delivery.

Mother’s Health Conditions That Raise Birth Injury Risk

A mother’s health significantly impacts birth injury risk. Several conditions deserve particular attention:

Obesity

Maternal obesity (typically defined as BMI over 30) complicates delivery in multiple ways. It makes fetal monitoring more difficult, increases the likelihood of macrosomia (since maternal weight gain often correlates with larger babies), and raises risks of other complications like gestational diabetes and preeclampsia.

Obesity also increases operative delivery rates and makes those procedures technically more challenging, potentially increasing injury risk during instrument-assisted birth or emergency cesarean delivery.

Maternal Age Over 35

Advanced maternal age brings higher rates of chromosomal abnormalities, but it also increases birth injury risk through other mechanisms. Older mothers have higher rates of:

• Gestational diabetes, which contributes to macrosomia.

• Hypertension and preeclampsia, which can require early delivery before the baby is full term.

• Uterine dysfunction during labor, leading to prolonged delivery or the need for augmentation with medications.

These aren’t guarantees of problems. Many women over 35 have uncomplicated deliveries. But the statistical risk increases enough that extra vigilance is warranted throughout pregnancy and labor.

Diabetes During Pregnancy

Both pre-existing and gestational diabetes affect fetal development. High maternal blood sugar leads to high fetal blood sugar, causing the baby to grow larger (especially the shoulders and trunk, not just overall size). This creates:

• Disproportionate growth that increases shoulder dystocia risk even when head size seems manageable.
• Potential for sudden drops in newborn blood sugar after birth, which can cause seizures if not managed properly.
• Higher rates of stillbirth and complications that may require early delivery.

Proper diabetes management throughout pregnancy significantly reduces these risks, but does not eliminate them entirely.

High Blood Pressure and Preeclampsia

Hypertension restricts blood flow to the placenta, potentially limiting oxygen and nutrients to the baby. Severe cases cause fetal growth restriction, meaning the baby is smaller and more vulnerable.

Preeclampsia, a dangerous pregnancy complication involving high blood pressure and organ damage, often requires early delivery to protect the mother’s life. This means delivering a premature baby with all the associated risks.

Both conditions also increase the likelihood of placental abruption, where the placenta tears away from the uterine wall before delivery, causing catastrophic bleeding and oxygen deprivation.

Physical and Anatomical Factors That Make Delivery More Difficult

Some anatomical realities simply make birth more mechanically difficult:

Small maternal stature or a narrow pelvis reduces the space available for the baby to pass through, increasing the chance of cephalopelvic disproportion and need for operative delivery.

First-time motherhood (nulliparity) means the birth canal hasn’t been stretched by a previous delivery. First births typically take longer and have higher rates of interventions. The mother’s body is going through processes it’s never experienced, and healthcare providers don’t have information about how her body responds to labor.

While these factors increase risk, they certainly don’t doom someone to a birth injury. Millions of small first-time mothers deliver healthy babies. But these factors do mean extra attention from healthcare providers is warranted.

How Prolonged Labor and Stalled Labor Lead to Birth Injuries

Labor dystocia, or difficult labor, encompasses situations where labor stalls, progresses too slowly, or stops advancing despite contractions. This might mean:

• The cervix stops dilating before reaching full dilation.
• Contractions become weak or irregular.
• The baby doesn’t descend through the pelvis despite strong contractions and full dilation.
• Prolonged labor (generally defined as more than 18-24 hours for first-time mothers or over 14 hours for subsequent births) exhausts both mother and baby. The longer labor continues, the higher the risk of:
• Fetal oxygen deprivation as the stress accumulates.
• Maternal exhaustion that makes pushing less effective.
• Infection as time passes, especially after membranes rupture.
• Need for interventions like forceps, vacuum, or emergency cesarean delivery under less-than-ideal circumstances.

On the opposite extreme, precipitous labor (extremely rapid labor lasting less than 3 hours) can also cause injury. The baby experiences sudden, intense pressure without time for the gradual molding that normally occurs. This can cause skull fractures, brain bleeding, or tearing of delicate connective tissues.

What Happens When Baby’s Head Is Too Large for the Birth Canal

Cephalopelvic disproportion occurs when the baby’s head is too large to fit through the mother’s pelvis, or the pelvis is too small for the baby’s head, regardless of actual measurements. It’s a mismatch that makes vaginal delivery difficult or impossible.

Sometimes this is predictable based on pelvimetry (measuring the pelvis) and ultrasound estimates of fetal size. In many cases, it only becomes apparent during labor when the baby simply doesn’t descend despite adequate contractions.

Cephalopelvic disproportion frequently leads to:

• Extended pushing phases that deprive the baby of oxygen.
• Attempts at operative vaginal delivery with forceps or vacuum.
• Emergency cesarean section, sometimes after hours of difficult labor.

The injury risk here comes both from the prolonged difficult labor and from the interventions required to complete the delivery.

Birth Injuries Caused by Forceps and Vacuum Extraction

Forceps and vacuum extractors are tools designed to help guide the baby out when delivery assistance is needed. When used appropriately by skilled providers, they can prevent more dangerous outcomes. But they also carry inherent risks:

Forceps are curved metal instruments placed around the baby’s head to provide traction and guidance. They can cause:

• Facial nerve damage, sometimes causing temporary or permanent facial paralysis.
• Skull fractures or depressions.
• Intracranial bleeding if excessive force is applied.
• Bruising and marking where the blades pressed.

Vacuum extractors use suction applied to the baby’s scalp to assist pulling. Risks include:

• Scalp swelling and bruising (caput succedaneum) or blood collection under the scalp (cephalohematoma).
• Subgaleal hemorrhage, a dangerous bleeding into the space between the skull and scalp that can be life-threatening.
• Retinal hemorrhages (bleeding in the eyes).
• Skull fractures, though less common than with forceps.

The critical question is often whether the instrument was necessary given the circumstances, whether it was used correctly, and whether it was continued too long when it wasn’t working.

How Emergency C-Sections Can Lead to Birth Injuries

Cesarean delivery is often the safest option when complications arise, but performing surgery in an emergency carries its own risks:

• Time pressure may lead to faster but potentially less precise technique.
• The baby may already be in distress when the decision is made, meaning oxygen deprivation may have already occurred.
• Surgical complications like excessive bleeding can compromise maternal stability and thereby affect the baby.

The key issue isn’t usually whether a cesarean was performed, but whether it was performed soon enough when warning signs appeared.

Birth Asphyxia and Oxygen Deprivation During Delivery

Birth asphyxia, or oxygen deprivation during delivery, is one of the most serious birth injury causes. The brain is particularly vulnerable to lack of oxygen. Even brief periods can cause lasting damage, and extended deprivation can be catastrophic.

How Umbilical Cord Complications Cause Oxygen Deprivation

The umbilical cord is the baby’s lifeline, carrying oxygenated blood from the placenta. Several cord problems can cause oxygen deprivation:

Cord prolapse occurs when the cord slips through the cervix before the baby, then gets compressed between the baby and the birth canal. This is an absolute obstetric emergency requiring immediate cesarean delivery. Every minute counts because the baby’s oxygen supply is completely or partially cut off.

Cord compression happens when the cord gets squeezed during contractions, temporarily reducing blood flow. Some compression is normal and well-tolerated, but repeated or sustained compression causes progressively worse oxygen deprivation. This often shows up on fetal monitoring as decelerations (drops in heart rate) coordinated with contractions.

Nuchal cord (cord wrapped around the neck) is actually quite common and usually harmless. However, if wrapped very tightly or multiple times, it can restrict blood flow and oxygen delivery.

True knots in the cord occur when the baby moves through a loop during pregnancy. If the knot tightens during delivery, it can obstruct blood flow.

Proper fetal monitoring should detect most cord problems through heart rate changes, but some occur suddenly without warning.

How Placental Abruption Causes Severe Birth Injuries

Placental abruption means the placenta separates from the uterine wall before the baby is born. This is catastrophic because the placenta is the oxygen and nutrient source. When it detaches:

• The baby loses oxygen supply immediately.
• The mother hemorrhages, potentially becoming unstable herself.
• Emergency delivery is required within minutes to prevent death or severe injury.

Risk factors include maternal hypertension, trauma, cocaine use, and previous abruption. It causes severe abdominal pain and bleeding, though bleeding isn’t always visible externally.

Even with immediate recognition and response, babies affected by significant abruption often suffer hypoxic brain injury because of the critical minutes it takes to perform an emergency cesarean delivery.

Uterine Rupture During Labor and Its Devastating Effects

Though rare (occurring in less than 1% of pregnancies), uterine rupture is a catastrophic event where the uterine wall tears open. Risk is highest in women with previous cesarean sections, particularly if they attempt vaginal birth after cesarean (VBAC).

When rupture occurs:

• The baby may be partially or completely expelled into the mother’s abdominal cavity.
• Both baby and mother lose blood rapidly.
• The baby’s oxygen supply is severed.

This requires immediate emergency surgery. The outcome depends entirely on how quickly the rupture is recognized and how fast surgical delivery can be accomplished.

Respiratory Problems in Premature Babies That Lead to Brain Injury

Premature infants haven’t developed adequate surfactant, a substance that keeps the tiny air sacs in the lungs open. Without it, the lungs collapse after each breath, making breathing extremely difficult.

Respiratory distress syndrome (RDS) causes oxygen deprivation that can lead to hypoxic brain injury. Modern neonatal care includes:

• Surfactant replacement given directly into the lungs.
• Respiratory support ranging from supplemental oxygen to mechanical ventilation.
• Careful oxygen monitoring, since too much oxygen can also cause damage (particularly to developing eyes and lungs).

Despite advances in neonatal care, severe prematurity remains a significant cause of oxygen-related birth injury.

What Is Hypoxic Ischemic Encephalopathy (HIE) and What Causes It

Hypoxic-ischemic encephalopathy (HIE) is brain damage caused by oxygen deprivation and reduced blood flow to the brain during birth. It’s one of the most serious birth injuries, often resulting in cerebral palsy, developmental delays, seizure disorders, or death.

HIE occurs on a spectrum from mild to severe:

• Mild HIE may cause temporary symptoms like jitteriness, poor feeding, or hyperalertness that resolve within days.
• Moderate HIE causes more significant symptoms including seizures, decreased muscle tone, and altered consciousness. Some babies recover completely; others have lasting impairment.
• Severe HIE involves prolonged seizures, severely abnormal muscle tone, and unresponsiveness. Severe HIE frequently causes permanent disabilities or death.

Treatment centers on therapeutic hypothermia (cooling treatment) if started within 6 hours of birth. This treatment reduces the extent of brain injury by slowing the cascade of cellular damage that continues even after oxygen is restored.

The causes of HIE are the causes of oxygen deprivation: cord accidents, placental abruption, prolonged difficult labor, uterine rupture, or failure of the medical team to respond appropriately to fetal distress signs.

Infection as a Birth Injury Cause

Infections during pregnancy and delivery can directly cause birth injuries or create conditions that lead to injury through other mechanisms.

Maternal Infections During Pregnancy and Labor

Chorioamnionitis is infection of the amniotic fluid and membranes surrounding the baby. It typically occurs when bacteria from the vagina ascend into the uterus, especially after membranes rupture.

Babies exposed to chorioamnionitis face risks including:

• Direct infection (neonatal sepsis or meningitis), which can cause brain damage, hearing loss, or death.
• An inflammatory response that makes the baby more vulnerable to hypoxic brain injury if oxygen deprivation occurs.
• Increased likelihood of premature delivery to treat the infection, bringing all the risks of prematurity.

Other maternal infections that can affect the baby include:

• Group B Streptococcus (GBS), bacteria commonly found in the vagina that can cause serious newborn infection if passed during delivery. Pregnant women are screened for GBS, and those who test positive receive antibiotics during labor.
• Urinary tract infections that progress to kidney infection and potentially bloodstream infection.
• Sexually transmitted infections like herpes, syphilis, or gonorrhea that can be transmitted during vaginal delivery.

The key is whether infections were properly screened for, diagnosed, and treated. Preventable infection that causes injury may constitute negligence.

Newborn Infections

Babies can develop infections during or after birth, including:

• Sepsis (bloodstream infection) that can quickly become life-threatening, affecting multiple organs including the brain.
• Meningitis (brain and spinal cord infection) that causes brain injury directly through inflammation and tissue damage.
• Warning signs of newborn infection include fever or low temperature, feeding difficulties, lethargy, irritability, and breathing problems. These symptoms require immediate medical attention.

Failure to recognize and treat newborn infections promptly can result in preventable brain injury or death.

Medical and Procedural Causes

Sometimes birth injuries result from how medical care was provided or from failures in monitoring and decision-making.

Improper Use of Delivery Instruments

Forceps and vacuum extractors require skill, appropriate selection of cases, and knowing when to stop. Improper use includes:

• Applying too many pulls or pulls with excessive force.
• Attempting operative vaginal delivery when the baby is too high in the pelvis.
• Continuing attempts when the instrument isn’t working instead of proceeding to cesarean.
• Using instruments when the clinical situation doesn’t justify the risks.
• Applying forceps or vacuum incorrectly, causing asymmetric pressure or pulling at wrong angles.

The medical literature provides clear guidelines about when operative vaginal delivery is appropriate and when cesarean is safer. Deviation from these standards may constitute negligence if injury results.

Failure to Monitor Fetal Well-Being

Continuous electronic fetal monitoring during labor tracks the baby’s heart rate and its relationship to contractions. This monitoring exists to detect oxygen deprivation before permanent damage occurs.

Failures in monitoring include:

• Not monitoring when the clinical situation requires it.
• Equipment problems that go unrecognized, creating gaps in data.
• Failure to interpret monitoring strips correctly.
• Recognizing concerning patterns but not acting on them appropriately or quickly enough.
• Not escalating concerns through the chain of command when the delivering provider doesn’t respond.

The fetal heart rate provides real-time information about how the baby is tolerating labor. Certain patterns such as particularly late decelerations (heart rate drops after contractions), prolonged decelerations, or absent variability, indicate the baby isn’t getting enough oxygen.

When these warning signs appear, the medical team must respond. The appropriate response depends on the severity and whether patterns are improving or worsening, but options include:

• Changing the mother’s position to relieve cord compression.
• Giving oxygen and fluids to the mother.
• Stopping Pitocin if it’s causing excessive contractions.
• Amnioinfusion (replacing amniotic fluid) if oligohydramnios is causing cord compression.
• Preparing for emergent delivery if patterns don’t improve.

The standard of care is clear: when fetal monitoring indicates distress, providers must act. Delay or inaction when monitoring shows a baby in trouble is one of the most common causes of preventable birth injury.

Delayed Recognition of Complications

Labor and delivery involve continuous assessment and reassessment. Complications can develop suddenly or gradually:

• Failure to recognize labor dystocia and continuing to wait when delivery should be expedited.
• Not identifying shoulder dystocia promptly or not performing appropriate maneuvers quickly.
• Missing signs of placental abruption, uterine rupture, or cord prolapse.
• Not recognizing that vacuum or forceps attempts aren’t working and continuing when cesarean should be performed.

The critical question is whether the medical team recognized complications as soon as a reasonable provider should have, and whether they responded as quickly as the standard of care requires.

Communication Failures

Birth injury sometimes results from poor communication:

• Between nurses monitoring the patient and physicians who make delivery decisions.
• During shift changes when important information isn’t properly handed off.
• Between departments (labor and delivery and operating room) when emergency cesarean is needed.
• Between team members during emergencies when rapid coordination is essential and breakdowns occur.

Healthcare providers must have systems to ensure critical information reaches the right people immediately. Communication failures that delay necessary interventions can cause preventable injury.

Anesthesia and Medication Errors

While less common, birth injuries can result from:

• Medication errors such as administering the wrong dose of Pitocin causing excessive contractions that deprive the baby of oxygen.
• Anesthesia complications that delay emergency delivery or cause maternal instability affecting the baby.
• Magnesium sulfate (given for preeclampsia) administered incorrectly, potentially affecting the baby.
• Failure to give necessary medications like antibiotics for GBS or infection.

Psychological Birth Trauma

Medical literature increasingly recognizes that birth trauma isn’t only physical. The experience of birth can be psychologically traumatic, affecting mental health and family bonding long-term.

What Constitutes Psychological Birth Trauma

Psychological birth trauma can result from:

• Feeling loss of control, dignity, or agency during birth.
• Experiencing severe pain without adequate relief or support.
• Believing one’s concerns were dismissed or that medical staff were unresponsive.
• Witnessing unexpected emergencies or fearing for one’s own or the baby’s life.
• Undergoing emergency interventions that felt frightening or weren’t adequately explained.
• Being separated from the baby after birth due to medical complications.
• This trauma can lead to post-traumatic stress disorder (PTSD), postpartum depression, anxiety, difficulty bonding with the baby, and fear of future pregnancies.

While not a physical injury to the baby, psychological birth trauma is a real and significant harm that deserves recognition and treatment. The emotional well-being of parents directly affects their capacity to care for and bond with their baby.

Social and Systemic Factors

Birth injury risk isn’t distributed evenly. Broader social factors influence outcomes:

Inadequate prenatal care means risk factors aren’t identified, maternal health conditions aren’t managed, and complications aren’t anticipated.

Socioeconomic barriers including poverty, lack of transportation, food insecurity, and housing instability affect maternal health and access to quality care.

Healthcare access disparities mean some families receive care in under-resourced facilities with less experienced staff or fewer options for specialty care.

Racial and ethnic disparities are well-documented, with Black and Native American mothers and babies experiencing significantly worse outcomes even when controlling for other factors. This points to systemic issues including implicit bias, differences in care quality, and the health effects of experiencing racism.

Limited English proficiency can create communication barriers affecting both routine care and emergency situations.

Rural healthcare deserts mean longer travel to facilities with obstetric services and potentially less experienced providers when volume is low.

These factors don’t excuse substandard medical care, but they provide context for understanding why birth injuries affect some communities disproportionately. Addressing birth injury requires both individual provider accountability and systemic changes to ensure all families access quality care.

Understanding How Multiple Causes Combine to Create Birth Injuries

Birth injuries rarely have one simple cause. More often, several risk factors combine with labor complications and sometimes with medical care issues to create the circumstances where injury occurs.

Understanding causes serves several purposes:

• It helps explain what happened, which is often the first thing families need to know.
• It identifies whether anything could have been done differently, which matters both for processing the experience and for determining if legal action is appropriate.
• It informs future pregnancies by identifying risks that may recur and need monitoring.
• It guides the medical team caring for the baby, since knowing the cause helps predict which problems may develop and what treatments may help.

No article can definitively explain any individual case. Every birth is unique, and determining causation requires detailed review of the complete medical record by qualified experts. But understanding the categories of causes and how they interact provides a foundation for the questions families need to ask and the information they need to gather moving forward.