The Premature Infant

Premature babies, typically referred to as "preemies" enter the word earlier than their full term peers, at 37 weeks or fewer gestation. Many preemies are born with low birth weight (under 5.5 lbs or 2500 grams) and require some extra medical attention or even a NICU (neonatal intensive care unit) stay.

There are many causes that can lead to prematurity, such as poor prenatal care, poor maternal nutrition, smoking, drug use, lack of weight gain, stress and maternal age (over 35 or under 19). Other causes such as illness, hormone imbalance, infections, physical abnormalities of the uterus or carrying multiples are not under a mother's control.

The March of Dimes currently reports that around 12% of babies are born prematurely and this rate has risen due to the number of multiple births (twins, triplets, quads) that have also increased recently. Due to modern advances in care for premature babies, the survival rate of babies weighing at least 2.5 lbs (800 grams) or more is around 90% and for babies weighing a little more than
1lb (500 grams) it is around 40-50%. The less a baby weighs at birth the higher the chance for medical and other complications.

Some common health problems that affect premature babies are as follows (not all inclusive)

Apnea- Apnea is usually caused by immaturity in the area of the brain that controls the ability to breathe. Almost all babies born at 30 weeks or less will experience apnea. During an apnea spell the baby may stop breathing, the heart rate may decrease and they may turn blue.

Hyperbilirubinemia - Infants with hyperbilirubinemia have high levels of bilirubin, a compound that results from the natural breakdown of blood. This high level of bilirubin causes them to develop jaundice, a yellow discoloration of the skin and whites of the eyes.

Low Blood Pressure - A common complication that occurs shortly after birth.

Anemia- Many premature infants lack the number of red blood cells necessary to carry adequate oxygen to the body.

Bronchopulmonary Dysplasia - Involves abnormal development of lung tissue and is characterized by inflammation and scarring in the lungs.

Nycrotizing Entercolitis - A gastrointestinal disease that mostly affects premature infants, NEC involves infection and inflammation that causes destruction of the bowel (intestine) or part of the bowel.

Respiratory Distress Syndrome -The infant's immature lungs don't produce enough surfactant, which allows the inner surface of the lungs to expand properly when the infant makes the change from the womb to breathing air after birth.

Infection - Preemies do not fight infection as well as full term babies.

Patent Ductant Arteriosus (PDA) - The ductus arteriosus is a short blood vessel that connects the main blood vessel supplying the lungs to the aorta, the main blood vessel that leaves the heart. Its function in the unborn baby is to allow blood to bypass the lungs, because oxygen for the blood comes from the mother and not from breathing air. In full-term babies, the ductus arteriosus closes shortly after birth, but it frequently stays open in premature babies. When this happens, excess blood flows into the lungs and can cause breathing difficulties and sometimes heart failure.

Retinopathy of Prematurity -The abnormal growth of the blood vessels in an infant's eye which can lead to visual impairments.

Some other concerns of the premature newborn are body temperature and nutrition, feeding and growth. Preemies don't have much body fat, so they are kept in incubators or in beds with radiant warmers to maintain their body temperature. Many preemies under 32-34 weeks gestation have difficulty feeding and are often tube fed before they can transition to the breast or bottle.

Many preemies spend weeks or months in the NICU (Neonatal Intensive Care Unit) and then sometimes transition to a step down unit and are then followed by developmental follow up clinics after their transition to home. Preemies are at much higher risk than their full term peers for developmental delays and are as much as 8 times more likely to have cerebral palsy. Preemies can also have later problems with learning, speech, self-regulation or sensory integration. All preemies should be evaluated by an early intervention team to determine the need for any services such as occupational therapy for feeding or physical therapy for motor delays.

There are many research studies on preemies and their ability to "catch up" with same age peers by the age of three and it is thought that many do catch up by at least age five. But just recently have researchers been able to follow the tiniest of preemies (those weighing around a pound) into the school years. While many babies will do just fine as they grow up, there is also a percentage (that varies depending on the studies you read) that will develop learning or behavioral problems in the school years. Many of these children also have ongoing medical complications. Research continues and is needed, on the outcomes for very low birth weight babies. Early intervention programs aim to intervene as early as possible to A) minimize the impact of the infant's disability if they have a specific diagnosis (such as cerebral palsy) B) minimize the ongoing risk factors (teaching parents helpful ways of understanding and helping their child) C) help an infant's present development go in the direction that will be the foundation for his future development (such as strengthening the muscles that will help a child walk in the future) D) strengthen and empower families and help them to cope with the stress of raising a preemie or a child with a disability. 

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