Overview of Preterm Labor
Labor that starts before the 37th week of pregnancy is preterm labor. Most pregnancies last between 37 and 42 weeks counting from the first day of the last menstrual period. Delivery before 37 weeks is called preterm or premature. If preterm labor leads to a preterm delivery, your baby may be at risk for health problems.
Your uterus prepares for delivery by tightening and relaxing during your pregnancy. These are contractions and most women feel them from time to time during their pregnancy. Occasional contractions that do not cause the cervix to change are not preterm labor.
Labor occurs when contractions are frequent or intense enough to cause cervical changes. The cervix is the opening to your uterus. When labor begins, uterine contractions cause the cervix to efface (thin) and dilate (open). Your cervix should stay closed until you approach your due date. This keeps your baby safely inside your uterus until it's mature enough to survive outside your womb.
Signs of Preterm Labor
The early signs of labor can be subtle and hard to detect. Many women are unaware of their uterus tightening. It is very important that you call your provider immediately if you think you are experiencing any symptoms of labor and you are less than 37 weeks gestational age. Preterm labor can often be treated and a preterm delivery avoided if symptoms are detected in time, and steps are taken to stop labor from progressing. Call your provider immediately if you experience any of the following signs of preterm labor:
- Contractions that are occurring 4 or more times in an hour
- Menstrual -like cramps
- Pelvic pressure
- Vaginal discharge that is watery, mucus-like or blood tinged
Risk Factors for Preterm Labor
Preterm labor occurs in about 8 - 10% of all pregnancies. It is important to know if you are at higher risk for preterm labor as early detection can help prevent progression to preterm delivery in some cases. Some of the risk factors for preterm labor are:
Higher Risk For Preterm Labor
- A multiple pregnancy (you are expecting twins or more)
- Incompetent cervix (a condition where the cervix is at risk for opening too soon)
- Teen pregnancy
- History of preterm labor or delivery
- Presence of uterine fibroids (benign growths) or other uterine abnormalities
- Vaginal bleeding in the second or third trimester
- Smoking or other substance use
- Underweight (weighing less than 50 kg) at start of pregnancy
- Age less than 20 or over 35
- Infection or illness
- History of second or third trimester pregnancy termination
Some women can experience preterm labor without feeling any contractions! A cervical exam by your prenatal care provider is the only way to rule out or confirm preterm labor.
Diagnosing Preterm Labor
The presence of uterine contractions accompanied by cervical changes (effacement or dilation) confirm the diagnosis of preterm labor. Remember that most women feel uterine contractions during their pregnancy. However, more than four contractions per hour, or contractions that are painful or intense, could indicate preterm labor. You should always call your provider immediately if you have any reason to suspect you might have preterm labor. Your doctor has the best chance of preventing a premature delivery the earlier your preterm labor is detected.
Treatment for Preterm Labor
Bedrest and lots of fluid are often the first treatment for preterm labor. Intravenous fluids can stop contractions in some women. Tocolytic agents (drugs that stop uterine contractions) are often used. Drug therapy is effective in stopping preterm labor in many cases if there is no bleeding or rupture of membranes (leaking from the "bag of waters" that surrounds your baby in your uterus). Hospitalization may be necessary. If a preterm delivery is a possibility, your doctor may give you a medication that will help your baby's lungs mature.
Management of preterm labor involves treating underlying causes, assessing maternal and fetal health and trying to delay delivery if it is in the best interest of mom and baby to do so. If the health of mom or baby is in imminent danger, sometimes allowing labor to continue is the only option.
Preventing Preterm Labor
Preterm labor cannot always be prevented, particularly if you have risk factors. However, there are a few things you can do to reduce your risk.
Reducing Risk Of Preterm Labor
- Start your prenatal care early and consistently keep all your scheduled appointments.
- Begin your pregnancy at a healthy weight for you. Discuss weight goals with your primary care physician before beginning pregnancy.
- Stay well hydrated throughout your pregnancy.
- Don't smoke or use drugs.
- Seek treatment immediately if you have any signs of infection or illness.
If you like this article, we'd be honored if you shared it using the button below.