Full Term Vs. Premature Infant Development

By Beth Greenwood
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Premature infants, commonly called preemies, are babies born before the 37th week of pregnancy. A normal pregnancy lasts 37 to 40 weeks and allows the infant to develop completely before birth. The smaller and younger a child is at birth, the higher the likelihood of complications or death, but today more than 90 percent of 800-gram preemies -- a weight equaling slightly less than two pounds -- can survive with good care, according to Kids Health. Even preemies of 500 grams -- slightly more than a pound --have a 60 percent chance of survival.

Special Needs

At birth, preemies have some special needs related to their development. Preemies don’t have much body fat and cannot maintain their body temperature even with lots of blankets, so neonatal intensive care nurseries, or NICUs, use special incubators with extra warmth. A preemie also needs extra nutrition -- preemies grow faster than full-term babies but their digestive systems are immature. Breast milk is the food of choice because it helps the baby fight infections and has proteins that promote growth. Preemies can’t always nurse, so the breast milk may need to be fed through a tube into the baby’s nose or stomach.

Jaundice and Other Problems

Many of a premature infant's internal organs aren’t fully developed, which can lead to jaundice -- a yellow color in the skin and eyes -- from a high level of bilirubin, a normal byproduct of red-blood-cell breakdown. The preemie’s immature brain may not send the right signals to keep the baby breathing, causing apnea. To compound this problem, preemies may not have enough red blood cells, which carry oxygen. Less-than-full-term babies may also have problems with low blood pressure, eye problems, heart problems, respiratory distress syndrome -- an inability to expand the lungs properly -- and infections. Most of these problems result from not being fully developed at birth.

Adjust Your Baby's Age

Full-term infants and preemies are individuals who each develop at their own pace. Just as some full-term children may walk and talk at different ages, preemies may also reach developmental milestones at different times than their peers. The American Academy of Pediatrics recommends that parents adjust the age of their preemie to determine whether the baby is within the normal range of development. AAP suggests that an adjusted age is the child’s actual age in weeks or months, minus the time from birth to the normal 40 weeks of pregnancy. A 12-week-old baby who was born six weeks early should have her milestones compared to those of a 6-week-old full-term infant.

Developmental Milestones

The AAP says a premature baby’s development should catch up to a full-term peer by the time they are each 2 years old. Prior to that time, remember to adjust your child’s age for normal milestones. For example, a full-term 4-month-old -- 16 weeks -- baby will usually laugh, squeal, reach for objects and lift herself with her arms when she is placed on her stomach. If your baby was born four weeks early, she may not achieve those milestones until she is 20 weeks from birth. By the time she’s 2 years old she should be walking alone, climbing stairs and speaking in two- or three-word sentences. If you are concerned about your baby’s development, consult your family doctor or pediatrician.

About the Author

Beth Greenwood is an RN and has been a writer since 2010. She specializes in medical and health topics, as well as career articles about health care professions. Greenwood holds an Associate of Science in nursing from Shasta College.