What is premature labor?

Paula Greer
Midwifery Nursing Specialist
Preterm labor is defined as labor that occurs between 20 and 37 weeks. Babies born prematurely often require hospitalization in a special care nursery. Although babies born after 37 weeks are not considered preterm, health care professionals and organizations like the March of Dimes advocate babies to wait till at least 39 weeks.
Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Technically, premature labor is defined as labor that starts before 37 weeks (the time when a baby's lungs are fully matured). If labor happens before 24 weeks, it is very unlikely (virtually impossible) for the baby to survive outside the womb for many reasons. In any case, the thing to remember is that in any preterm situation, something is going on inside the womb that is not agreeing with the baby, and the baby probably decides it's safer outside than in.

YOU: Having a Baby: The Owner's Manual to a Happy and Healthy Pregnancy

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YOU: Having a Baby: The Owner's Manual to a Happy and Healthy Pregnancy

Few life experiences feature the extreme emotional swings as pregnancy does -- it's a monumental mix of both intense excitement and skip-a-beat anxiety. If you're like most, you scour web sites, read...
Dr. Deborah Raines, MSN
Nursing Specialist

Preterm labor is the onset of labor between the 20th and 37th week of pregnancy. To meet the criteria of labor, the contractions must be regular in occurrence and cause the cervix or the lower end of the uterus to efface and dilate earlier than normal. Early recognition of the onset of preterm labor is important in beginning a treatment plan in hopes of preventing a preterm birth.

Preterm labor is labor that happens too soon, before 37 weeks of pregnancy. Babies born this early are called premature. Premature babies can have serious health problems at birth and later in life.

Learn the signs and symptoms of preterm labor and what to do if they happen to you at: 

Premature labor is when labor occurs earlier in the pregnancy than is normal—from 20 to 36 weeks. Persistent uterine contractions cause the cervix to efface (thin) and/or dilate (open). This can result in the premature birth of the baby. Babies born more than three weeks before their due date can have serious problems breathing, feeding and keeping warm. All pregnant women are at some risk for preterm labor.

Dr. Melissa A. Brown, MD
OBGYN (Obstetrician & Gynecologist)

Premature labor is going into labor before a baby is due. A full-term baby is one that is delivered somewhere between 37 to 42 weeks pregnant, whereas your due date is set at approximately 40 weeks gestation. So premature labor occurs before 37 weeks. When we're most worried is when it is even earlier than that—before 34 weeks.

Deborah Flansburg, CNM
Nursing Specialist

Early labor (or premature labor) in pregnancy is a time when the uterus is contracting but not making a lot of process towards the delivery. Contractions may be far apart, they may be short, and they may be more of a pressure sensation than a painful sensation. A lot of women experience the pain in their back and in their legs more than in their abdomen and pelvis. The contractions are generally five to ten minutes apart and last thirty to sixty seconds. At this point, the labor can stop, because it's early and may be called a false labor.

If it is a true labor, then it continues to increase in intensity over a period of time until you get to what we call active labor, where the contractions are two to three minutes apart, and each contraction lasts for about sixty seconds and it is felt throughout the woman's body. Her heart rate increases, the uterus becomes tight and painful, she feels it in her back, in her legs and her pelvis.

Boston Women's Health Book Collective
Administration Specialist

About eight out of every one hundred women go into premature labor, defined as labor before 37 weeks. If this progresses to premature birth, the baby may need special care. The closer the baby's birth is to "full term," or 39 weeks, the lower its risk of medical complications. Babies who are born before 28 weeks have a greater risk of dying, and those who survive may have lasting medical problems. Fortunately, the care in neonatal intensive care units has greatly improved the healthy survival of very premature infants.

"Preemie" babies are vulnerable to many complications, such as breathing, neurological, and intestinal problems. Depending on how early the baby is born, she or he will be evaluated by a pediatrician immediately after birth and may need to be cared for in the neonatal intensive care unit (NICU).

Our Bodies, Ourselves: Pregnancy and Birth

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Our Bodies, Ourselves: Pregnancy and Birth


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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.