There are many factors which will determine the preemies
chances for survival. Here are just a few very important
factors:
-
Gestational age at birth (number of completed weeks of
pregnancy)
-
The weight of the baby
-
Indications of breathing problems or not
-
The presence or absence of congenital abnormalities or
malformations
-
The presence of any severe diseases, especially infection
Gestational age is usually most important because it determines
if the infant's organs, particularly the lungs, have developed
enough to allow the baby to live within the limits of current
technology.
Your baby's doctor will be able to give you the best estimate of
your infant's chances since he/she can take into consideration
many of the above factors.
But, no estimate is perfect. Some babies suddenly get sick
and die unexpectedly; others defy all odds. General estimates of
survival for live born infants who receive neonatal intensive
care in the USA in the late1990's are:
| Completed Weeks Gestation At Birth |
Survival |
|
|
0% |
|
|
0-10% |
|
|
10-40% |
|
|
40-70% |
|
|
50-80% |
|
|
80-90% |
|
|
>90% |
|
|
>95% |
|
|
>98% |
* Most babies at 22 weeks are not resuscitated because survival
without major disability is so rare.
A baby's chances for survival increases 3-4% per day between 23
and 24 weeks of gestation and about 2-3% per day between 24 and
26 weeks of gestation. After 26 weeks the rate of survival
increases at a much slower rate because survival is high
already.
What other factors influence survival?
Other factors may influence survival by altering the rate of
organ maturation or by changing the supply of oxygen to the
developing fetus.
-
Rupture of the fetal membranes before 24 weeks of gestation with
loss of amniotic fluid markedly decreases the baby's chances of
survival even if the baby is delivered much later.
-
Male infants are slightly less mature and have a slightly higher
risk of dying than female infants.
-
For a given weight, African-American babies have a slightly
better survival than Caucasian; most other races are
intermediate between the two
-
Diabetes in the mother, if not well controlled, slows organ
maturation and these infants have a higher mortality.
-
Severe high blood pressure before the 8th month of pregnancy may cause changes in the placenta, decreasing the delivery of nutrients and/or oxygen to the developing fetus and leading to problems before and after delivery.
|