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Quick Facts

Premature Baby


The Manual's Editorial Staff

Last full review/revision Dec 2019| Content last modified Dec 2019
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What is a premature baby?

"Pre-" means before, and "mature" means fully grown.

A premature baby is born too early. A full pregnancy lasts 37 to 40 weeks, so a premature baby is born anytime before the 37th week of pregnancy.

The more premature babies are, the more likely they are to have complications at birth and later. Babies born before 23 weeks probably won't live.

  • Because premature babies had less time to grow in the womb, their organs are not fully developed

  • Premature babies may have trouble breathing and feeding and are more likely to get infections

  • Many premature babies have no long-term problems

  • Very premature babies have a higher chance of long-term health problems such as cerebral palsy, hearing problems, or learning disorders

  • Very premature babies may need to be in an incubator to keep warm, be on a ventilator to help them breath, and be fed through a tube in their nose

  • Premature babies stay in the hospital until they can eat normally, are gaining weight, and no longer need an incubator

  • Seeing your doctor regularly during pregnancy lowers your chance of having a premature baby

What causes a baby to be born prematurely?

Most of the time, there's no clear reason why a baby is born too early.

The chances of having a premature baby are higher if the mother:

  • Had a previous premature baby

  • Has had multiple miscarriages or abortions

  • Has other health problems, such as preeclampsia or heart or kidney disease

  • Has an untreated infection (such as a urinary tract infection)

  • Is having twins or triplets

  • Used in vitro fertilization (IVF) to get pregnant

  • Smokes cigarettes

  • Doesn't get good prenatal care

What are symptoms of a premature baby?

Premature babies look a little different than full-term babies. They usually:

  • Weigh between 1 and 5.5 pounds (500 to 2500 grams)

  • Have a head that looks large compared to the rest of their body

  • Lack fat under their skin

  • Have thin, shiny, pink skin

  • Have veins visible through their skin

Premature babies often:

  • Breathe quickly and may pause for seconds at a time (apnea)

  • Have trouble regulating their body temperature

  • Have trouble sucking and swallowing

What complications do premature babies have?

Premature babies get complications because their organs aren't fully developed. The more premature they are, the more complications they get.

  • Brain complications: Weak breathing, trouble sucking and swallowing, brain bleeding

  • Digestive tract complications: Spitting up too much, bleeding intestines, yellow skin (jaundice)

  • Immune system complications: Infections in their bloodstream (sepsis) or around their brain (meningitis)

  • Lung complications: Lungs clogged with fluid (respiratory distress syndrome)

  • Eye complications: Bleeding and scarring in the retina (the seeing part of the eyes), a problem called retinopathy of prematurity

Most complications go away after a while. But babies who had severe complications may keep having problems with their breathing or vision.

How do doctors treat premature babies?

Doctors will care for your baby in the hospital in a special unit for sick newborns. It's called a NICU, which stands for neonatal intensive care unit. They'll also:

  • Put your baby in an incubator to help keep the baby warm

  • Give medicine into your baby's lungs to help your baby breathe, and sometimes put a tube in the baby's nose or mouth attached to a breathing machine (ventilator)

  • Feed your baby through a vein or feeding tube until your baby can suck and swallow

  • Put the baby under special UV lights to treat jaundice

How can I keep my baby from being premature?

You can lower the chance of your baby being premature by:

  • Going to all of your prenatal doctors' visits

  • Following a healthy diet

  • Not drinking alcohol

  • Not using tobacco or drugs

If you go into labor early, your doctor may give you medicine to:

  • Slow down your labor

  • Help your baby’s lungs develop faster

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version


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