Every year it is estimated that about 15 million children are born preterm (before the 37 week of pregnancy). This number is increasing progressively.
Preterm birth is number one cause of death under 5 years of age.
In the world about 1 million of children die a year for that cause.
Prematurity is also the cause of increased infant morbidity. In the world the number of infant born preterm varies between 5 to 18%. (1)
4 categories of prematurity are recognized according to the gestational age in which childbirth occurs.
about in 0.25% of pregnancies
about in 0.6% of pregnancies
about in 0.3% of pregnancies
In Italy the percentage of preterm birth is around 8%.
It is now known that preterm birth depends on two major causes.
The second is related to a series of clinical causes and concauses that can determine preterm birth even in subjects that are not intended. These conditions obviously aggravate and anticipate the event of birth in those genetically predisposed.
TAB. 1 Traditionally recognized causes of preterm birth
SOCIO-DEMOGRPHIC FACTORS (*)
|B||PREGRAVID MEDICAL CONDITIONS||
|E||ENVIRONMENTAL TOXIC CAUSES(*)||
|F||INFLUENCE OF PERSONAL CONDUCT (*)||
|* with significant variations and differences between races and populations