Understanding Preterm Labor and Birth -- the Basics
What Are Preterm Labor and Premature Birth?
A normal pregnancy lasts about 40 weeks after the first day of the last period (38 weeks after fertilization). Contractions and dilation (opening) of the cervix before 37 weeks of pregnancy is called preterm labor. Babies born before 37 weeks of pregnancy are called premature babies.
Premature delivery may be preceded either by contractions or premature rupture of the fetal membranes (PROM), when the water breaks before labor begins.
The danger of preterm labor is that it may lead to the premature birth of a baby that has not fully developed, putting the baby at a higher risk for health complications. About 10% of all pregnancies result in premature birth. The majority of serious complications or infant deaths are due to consequences of premature birth. Unfortunately, the number of babies born prematurely in the U.S. has risen in recent years.
Preterm labor can be extremely frightening, because parents-to-be quite naturally fear that their baby will be born too early and suffer the problems of prematurity. If your baby is born too soon, there is a good chance that his or her lungs will be underdeveloped. If so, he or she will need to be put onto a ventilator to help with breathing. Receiving oxygen through a ventilator can lead to complications, so doctors try to get premature infants off the ventilator as soon as possible.
Your baby may also have trouble maintaining a normal body temperature, may become hypothermic (too cold), and will need to be kept warm. If your baby is born too early to coordinate the muscles to suck and swallow, he or she will have to be fed intravenously, through a needle in a vein, or through a tube passed through the nose and throat and into the stomach.
A premature baby may also develop complications such as:
- Bleeding in the brain
- An increased risk of infections, especially meningitis and sepsis (a serious, widespread infection throughout the body)
- Problems with kidney function
Premature babies are at higher risk for long-term complications, which may include vision impairment or blindness, hearing impairment, cerebral palsy, and chronic lung problems. The earlier the baby is born, the more likely that she will have these problems.
Who Has Preterm Labor?
Although there have been many advances in caring for premature babies, there has been little significant improvement in treating the problem of preterm labor. Medical science doesn't completely understand why some women go into labor or break their water early. There's no completely accurate way to predict which women will do so or prevent them from giving birth prematurely. In some cases, an infection may be involved. In others, it may be an abnormally short cervix or a combination of factors. In about half of all cases, no cause can be found.