Why are babies born premature?

SamanthaWhy do some babies come early?
Sarah: Premature birth occurs in around 1 in 12 pregnancies, yet we still have very little understanding of what causes it, and are only now making inroads into predicting and preventing it. There are three distinct scenarios. 1. Is women who go into labour before they should and give birth. 2. Is women who experience preterm rupture of their membranes and waters breaking. 3. Women who have their babies early, usually via caesarean section, because of some medical risk to the mother or baby, such as pre-eclampsia, growth restriction or placental abruption.