What is the cause of premature kids?

Many reasons: exist for premature delivery. (defined as delivery before 37 completed weeks of gestation). The causes include complex interactions of many factors including genetic and environmental situations. Added to that is the limitation of accurate prediction of gestational age in spite pf many measures. Cigarette smoking is, so far, the major preventable cause of preterm birth. Infection is another trigger as is poor nutrition, poor maternal health, lack of prenatal care, and extremely young age of mother.