The normal gestation period for a fetus is about 39 weeks. Any child born before the 37^th week of gestation is considered premature, according to the March of Dimes Birth Defects Foundation. This date is calculated based on the first day of the woman’s last menstrual period and confirmed by ultrasound. Accurate dating of a pregnancy is essential to diagnosing a premature birth. Without the additional time in the mother’s uterus to develop and mature, the baby is at a higher risk of medical and developmental complications.

The most common complication of premature delivery is underdeveloped lungs, which is often referred to as respiratory distress syndrome (RDS). This occurs because the substance surfactant is not adequately produced and the lungs cannot remain expanded. In addition, premature birth is the leading cause of neonatal death during the first month of life.

There are more than 480,000 babies born prematurely each year in the United States, according to the U.S. Centers for Disease Control and Prevention (CDC). In about half of all premature births, physicians are unable to determine what causes a woman to go into labor early. However, certain known risk factors can cause an early delivery. Some of these include:

• Little or no prenatal care
• Carrying multiples (e.g., twins, triplets)
• Maternal age (less than 18 or over 40 years)
• A history of preterm deliveries
• Smoking or other forms of tobacco use
• Certain abnormalities of the uterus or cervix

Although most women carry their babies to full term, pregnant women (especially those in high-risk categories) should be aware of the symptoms of premature labor. These include contractions that are 10 minutes apart or less, menstrual-like cramps, dull back pain, pressure in the pelvic area, stomach cramps, watery fluid leaking from the vagina or other vaginal discharge. Any woman who suspects she is entering premature labor should contact her obstetrician-gynecologist (ObGyn) immediately.

Although some ObGyns may recommend bed rest or other therapies, these recommendations have shown inconsistent results in preventing preterm births. In fact, according to the American College of Obstetricians and Gynecologists, no reliable preventive therapies have proven to be effective in reducing preterm birth rates.