What is preterm or premature birth?

Preterm or premature delivery is a birth that is before 37 weeks of the pregnancy or more than three weeks before a baby's due date.

Throughout the course of a 40-week pregnancy, there are many important growth and developments including the final months and weeks of the pregnancy. Although most babies born a few weeks early do well with no health consequences, the earlier they are born, the more health problems they will have.

That is why it's important to learn more about preventing preterm birth. A premature or preterm baby is more likely to have certain complications such as:

• Brain issues
• Lung issues 
• Bowel problems
• Jaundice
• Longer hospital stays

The more preterm a baby is born, the more severe his or her health problems are likely to be. Although babies born very preterm are a small percent of all births, preterm delivery is the most frequent cause of infant deaths. Some premature babies require special care and spend weeks or months hospitalized in a neonatal intensive care unit (NICU). Those who survive may face lifelong problems such as:

• Intellectual disabilities
• Cerebral palsy
• Breathing and respiratory problems
• Vision and hearing loss
• Feeding and digestive problems

Warning signs of preterm labor

In most cases, preterm labor begins unexpectedly and with no known cause. The warning signs are:

• Contractions (abdomen tightens like a fist) every 10 minutes or more often
• Change in vaginal discharge (leaking fluid or bleeding from the vagina)
• Pelvic pressure—the feeling that the baby is pushing down
• Low, dull backache
• Cramps that feel like a menstrual period
• Abdominal cramps with or without diarrhea

Risk factors for premature labor

Many premature births happen without risk factors, even if a woman does everything "right." There are still risk factors that increase the risk of preterm birth. They include:

• Prior preterm birth
• Multiples (twins, triplets, etc)
• A short cervix
• Prior cervical surgery
• Certain infections
• Polyhydramnios (too much amniotic fluid)
• Certain ethnic groups
• Hypertension
• Diabetes
• Cigarette smoking 
• Alcohol use  

Check out the babyMed Preterm Delivery Risk Calculator and find out your risk of a preterm birth!

This NICHD Extremely Preterm Birth Outcome Calculator will provide you with additional general information on chances of survival and disability, though outcomes vary depending on individual circumstances and location of birth.

Lower your risk

You can do certain things to help their health and lower the risk of having a premature baby:

• Quit smoking and avoid alcohol and drugs. 
• See your health care provider for a medical checkup before pregnancy. 
• Work with your doctor to control diseases such as high blood pressure or diabetes. 
• Get prenatal care early, as soon as you think you may be pregnant, and throughout the pregnancy. 
• Discuss concerns during pregnancy with your health care provider, and seek medical attention for any warning signs or symptoms of preterm labor. 

Doctors sometimes decide to deliver a baby early because of concerns for the health of the mother or the baby. Medical intervention for an early delivery should only be considered when there is a medical reason to do so.