What are the causes and risks of thepremature infant?

Mothers with certain risk factors are statistically more likely to give birth to a low-birth-weight infant. These factors include the following:

* abusing drugs or being addicted to drugs
* being single
* being very thin, or less than 100 pounds, before pregnancy
* being younger than 16 years of age or older than 35 years of age
* dealing with high levels of stress
* having already given birth to a low-birth-weight infant
* having African American ancestry
* having had few years of schooling
* having poor weight gain, or less than a 10-pound gain, during pregnancy
* living in poverty
* receiving no prenatal care
* smoking cigarettes
* using alcohol
* waiting only a short time between pregnancies

Some babies have factors themselves that make them more likely to be born early. These factors include being one of multiple babies in the same womb, such as twins or triplets. The baby may have physical problems or a bloodstream damaged by infection.

Sometimes there are problems with a mother's womb. The placenta may not be adequate to support the baby to full term. The placenta may be in an unusual location, such as near to or obstructing the outlet to the womb (placenta previa). When the mother has a chronic illness like diabetes, congestive heart failure, or high blood pressure, she is more likely to deliver early. Certain infections in the mother, such as genital herpes or syphilis, can also trigger a premature birth.