What is a preterm baby?

Online Q&A
Updated November 2015

Q: What does “preterm” mean?

A: Preterm refers to a baby born before 37 weeks of pregnancy have been completed. Normally, a pregnancy lasts about 40 weeks.

Q: How many babies are born preterm every year and where?

A: Preterm birth is a global problem. It occurs in high, low, and middle-income countries. About 15 million babies are born preterm each year; that is more than 1 in 10 babies worldwide. 60% of them are born in sub-Saharan Africa and South Asia.

Q: How do preterm births occur?

A: Most preterm births happen spontaneously, but some are due to early induction of labour or caesarean birth, whether for medical or non-medical reasons.

Q: Is there a way to tell if you are at risk of having a preterm baby?

A: There is no test that can accurately predict who might have a preterm birth. We do not fully understand the causes of preterm births.

There are several factors that may put a pregnant woman at higher risk of a preterm birth, including a previous preterm birth, multiple pregnancies such as twins, triplets, etc, some chronic medical conditions such as high blood pressure, diabetes and infections. Pregnancy in adolescence is a major risk factor for preterm birth.

Q: Can a pregnant woman’s lifestyle put her at risk of a preterm birth?

A: Women who smoke cigarettes, drink alcohol or take other recreational drugs are at a higher risk of having preterm babies. Stress from any cause is also known to increase a woman’s risk of having preterm birth.

Q: How many preterm babies could be saved?

A: Around 1 million preterm babies die each year. Those babies who survive can face lifelong physical, neurological or learning disabilities, often at great cost to families and society.

An estimated three-quarters of these preterm babies could survive if they had access to proven and often inexpensive care – like warmth, breastfeeding support, and basic care for infections and breathing difficulties.

Though preterm births occur in high-income countries, access to these proven interventions means that almost 9 out of every 10 preterm babies survive in those settings in sharp contrast to about 1 out of 10 in low-income countries.

Q: Why do preterm babies need special care?

A: Preterm babies are not fully prepared to live in the world outside their mother’s womb. They get cold more easily and may need more help feeding than full-term babies. Because their bodies are not yet fully developed, they may have problems breathing and can also suffer from other complications including infections.