(This is the first of two stories about premature babies.)
Great strides have been made since I started practicing pediatrics both in the prevention of prematurity and in the care of premature infants.
About 96% of babies born after 28 weeks’ gestation now survive. Although the percentage of babies delivered early keeps dropping every year, more than 11% are still born premature.
A baby’s due date is usually considered to be 40 weeks after an expectant mother’s last period. How many weeks pregnant an expectant mother happens to be is referred to as her (or the baby’s) gestational age, or gestation.
A baby is considered full-term if he makes it to 37 weeks gestation before being born. Premature infants, then, are those born before 37 weeks gestation.
Some causes of prematurity are preventable. These include smoking, abusing alcohol, abusing drugs, poor nutrition, poor weight gain, poor prenatal care, stress, pregnancy before 16 years of age or pregnancy after 35 years of age.
Some causes of premature birth are not preventable. These include some maternal hormone imbalances, chronic illnesses such as insulin-dependent diabetes mellitus, having a structurally abnormal uterus or cervix, having pregnancy-induced hypertension, or contracting certain infections during pregnancy.
A premature infant will look different than a full-term infant.
She may look thin, since she hasn’t had time to put on a lot of body fat. Her skin may be smooth and translucent.
Sometimes the baby will be covered with fine hair called lanugo.
The ears are often soft and flexible. She may appear to be somewhat floppy. She may also breathe fast or irregularly.
Premature male infants often have smooth scrotums. Their testicles may not have dropped into them yet. Premature girls may have prominent clitorises.
Most premature infants born before 35 weeks gestation end up going to the neonatal intensive care unit (NICU) for more specialized care.
Some babies born at 35 week gestation or after may need to go there, too.
Because a premature infant does not usually have much body fat, temperature instability is a major concern.
The baby will be under a warmer and later probably in an incubator to keep his temperature up.
Premature infants can also have problems with anemia, jaundice, and hernias (umbilical and inguinal).
Despite all the health issues preemies face, progress continues to be made in both preventing and treating prematurity.
Dr. Charles Ison is a University of Kentucky graduate who has practiced in his hometown of Lexington since 1993. He is a partner in Pediatric and Adolescent Associates.
(Next month: Preemies and breathing, feeding and their immune systems.)