While not all premature babies experience complications, being born too early can cause short-term and long-term health problems for preemies. Generally, the earlier a baby is born, the higher the risk of complications. Birth weight plays an important role, too. Some problems may be apparent at birth, while others may not develop for weeks or months.

Short-term complications

In the first weeks, the complications of premature birth may include:

  • Breathing problems. A premature baby may have trouble breathing due to an immature respiratory system. In some cases, breathing difficulties can prevent other immature organs in the body from receiving enough oxygen. If the baby's lungs lack surfactant — a substance that allows the lungs to expand — he or she may develop respiratory distress syndrome. This condition primarily affects infants born before 35 weeks. Preemies, especially those born between 23 and 32 weeks, may also develop chronic lung disease known as bronchopulmonary dysplasia. In addition, some preemies experience prolonged pauses in their breathing, known as apnea.
  • Heart problems. The most common heart problems premature babies experience are patent ductus arteriosus (PDA) and low blood pressure (hypotension). PDA, which tends to affect babies born before 30 weeks, is a persistent opening between two major blood vessels leading from the heart. While this heart defect often closes on its own, left untreated it can cause too much blood to flow through the heart and cause heart failure as well as other complications. Low blood pressure may require adjustments in intravenous fluids, medicines, and sometimes blood transfusions.
  • Brain problems. Babies born before 28 weeks are at risk of bleeding in the brain, known as an intraventricular hemorrhage. Most hemorrhages are mild and resolve with little short-term impact. But some babies may have larger brain bleeding which causes permanent brain injury. Larger brain bleeds may lead to fluid accumulation in the brain (hydrocephalus) over a number of weeks. Some babies who develop hydrocephalus will require an operation to relieve the fluid accumulation.
  • Temperature control problems. Premature babies can lose body heat rapidly; they don't have the stored body fat of a full-term infant and they can't generate enough heat to counteract what's lost through the surface of their bodies. If body temperature dips too low, hypothermia can result. Hypothermia in a preemie can lead to breathing problems and low blood sugar levels. In addition, a preemie may use up all of the energy gained from feedings just to stay warm, not to grow bigger. That's why smaller preemies require additional heat from a warmer or an incubator until they're larger and able to maintain their temperature without assistance. After you bring your baby home, you won't need to keep your house or apartment any warmer than you typically would.
  • Gastrointestinal problems. Preemies are likely to have immature gastrointestinal systems. The earlier a baby is born, the greater his or her risk is of developing necrotizing enterocolitis (NEC). This potentially serious condition, in which the cells lining the bowel wall are injured, primarily occurs in premature babies after they start feeding. Premature babies who receive only breast milk have a much lower risk of developing NEC.
  • Blood problems. Preemies are at risk of blood problems such as anemia and infant jaundice. Anemia is a common condition in which the body doesn't make enough red blood cells. While all newborns experience a slow drop in red blood cell count during the first months of life, the decrease may be greater in preemies. More severe anemia may occur if your baby has a lot of blood taken for lab tests.

    Infant jaundice is a yellow discoloration in a newborn baby's skin and eyes that occurs because the baby's blood contains an excess of a yellow-colored pigment of red blood cells (bilirubin). Infant jaundice is common in babies born before 38 weeks.

  • Metabolism problems. Premature babies often have problems with their metabolism. Some preemies may develop an abnormally low level of blood sugar (hypoglycemia). This can happen because preemies typically have smaller stores of glycogen (stored glucose) than do full-term babies and because preemies' immature livers have trouble producing glucose.
  • Immune system problems. An underdeveloped immune system, common in premature babies, can lead to infection. Infection in a premature baby can quickly spread to the bloodstream causing sepsis, a life-threatening complication. As a result, when a preemie's condition is getting worse, your baby's doctor might check for an infection — even if there's no fever. Often, in such situations, your baby may be given antibiotics until it's apparent that there's no infection.

Long-term complications

In the long term, premature birth may lead to these complications:

  • Cerebral palsy. Cerebral palsy is a disorder of movement, muscle tone or posture that is caused by injury to a preemie's developing brain either during pregnancy or while the baby is still young and immature. Brain injury from poor circulation, insufficient oxygen supply, undernourishment or infection can all lead to cerebral palsy or other neurological problems.
  • Impaired cognitive skills. Premature babies are more likely to lag behind their full-term counterparts on various developmental milestones. Upon school age, a child who was born prematurely might be more likely to have learning disabilities.
  • Vision problems. Preemies born before 30 weeks may develop retinopathy of prematurity (ROP), a disease that occurs when blood vessels swell and overgrow in the light-sensitive layer of nerves at the back of the eye (retina). Sometimes the abnormal retinal vessels gradually scar the retina, pulling it out of position. When the retina is pulled away from the back of the eye it's called retinal detachment, a condition that, if undetected, can impair vision and cause blindness.
  • Hearing problems. Premature babies are at increased risk of some degree of hearing loss. All babies will have their hearing checked before going home.
  • Dental problems. Preemies who have been critically ill are at increased risk of developing dental problems, such as delayed tooth eruption, tooth discoloration and improperly aligned teeth.
  • Behavioral and psychological problems. Children who experienced premature birth are more likely than full-term infants to have certain behavioral and psychological problems, such as attention deficit hyperactivity disorder, depression or generalized anxiety, and difficulties interacting with kids their own age.
  • Chronic health issues. Premature babies are more likely to have chronic health issues — some of which may require hospital care — than are full-term infants. Infections, asthma and feeding problems are more likely to develop or persist. Premature infants are also at increased risk of sudden infant death syndrome (SIDS).

For some premature babies, difficulties may not appear until later in childhood or even adulthood. Not performing well in school is often a prime concern. Some studies suggest that premature babies may face an increased risk of type 2 diabetes and cardiovascular disease in adulthood.

Dec. 29, 2011

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