Every year, over 15 million babies are born premature (under 37 weeks) and over 1 million die because of prematurity.

According to a study in The Lancet , there are five interventions for all 39 countries with higher development that could lead to a 5% relative reduction of preterm birth rate from 9·59% to 9·07% of livebirths:

1. smoking cessation (0·01 rate reduction), 
2. decreasing multiple embryo transfers during assisted reproductive technologies (0·06), 
3. cervical cerclage (0·15), 
4. progesterone supplementation (0·01), and 
5. reduction of non-medically indicated labour induction or caesarean delivery (0·29). 

These findings translate to roughly 58 000 preterm births averted and total annual economic cost savings of about US$3 billion.