Lynette Sabin started feeling frequent contractions in the last trimester of her pregnancy. The Colorado Springs mom remembers being nervous—she hadn’t felt anything like it with her two previous pregnancies. At 34 weeks, Sabin’s doctor explained that she had an irritable uterus and put her on bed rest. “I couldn’t mop, vacuum, sweep,” recalls Sabin. “The first day I thought ‘Yippee, this is going to be great,’ but then nervousness set in and I worried I might miss a signal.” Sabin’s son was born three weeks early, a week after she was taken off bed rest. “He was just a little guy, but he was healthy.”
Although not a clinical term, irritable uterus describes irregular contractions during pregnancy—before the due date. Most times these contractions are merely a nuisance, but sometimes, as in Sabin’s experience, they are an indication of preterm labor.
What is an irritable uterus?
Made up of smooth muscles, the uterine wall performs an amazing feat once labor begins. The muscle sends out patterned contractions, which usually last around 30 to 90 seconds every three to five minutes. These contractions help push the baby out of the uterus and lead to delivery.
“‘Uterine irritability’ is a term used to describe the phenomenon that prior to the onset of labor, the uterus can contract in a disorganized fashion (during pregnancy),” explains Dr. Laura Klein, an OB-GYN at the University of Colorado School of Medicine. “Rather than strong contractions that come and go every few minutes there can be kind of a constant low level twitching of the muscle.” Most of the time these contractions are simply a nuisance and don’t lead to labor.
Uterine irritability should not be confused with preterm labor. A uterus that contracts might be doing just that, contracting. As long as these contractions are not affecting the cervix—by pulling it open or shortening it—there is not risk for early labor. If you are experiencing early contractions, your doctor will be able to evaluate the contractions to see if they are cause for concern.
How common is irritable uterus?
“Uterine contractions are a normal thing,” notes Dr. Raul Artal, Professor and Chairman of the Department of Obstetrics and Gynecology and Women’s Health at the St. Louis University School of Medicine. Many times your uterus might be contracting without you even noticing it.
What are the risks associated with an irritable uterus?
The danger with an irritable uterus is the connection to preterm labor. Early labor happens when contractions dilate the cervix. An irritable uterus usually does not cause the cervix to dilate, but persistent, intense contractions can lead to an early delivery. Women with uterine irritability experience preterm labor at a slightly higher percentage than the general population of pregnant women (18.7 percent versus 11 percent).
What are the symptoms of irritable uterus?
According to Dr. Klein, you should see your OB-GYN or midwife right away if you experience any of the following symptoms before you reach 37 weeks in your pregnancy:
- Painful contractions or contractions that occur more than four times in an hour
- Vaginal bleeding or watery leakage from the vagina
- Pressure on your pelvis
- Lower back pain that seems to have a pattern, which may signal contractions
- Slowed fetal movement—less than 10 movements in a two-hour period
How do doctors test irritable uterus?
Most likely your doctor will evaluate your uterus with a monitor to determine if your contractions pose a preterm labor risk. Pressure-sensitive belts are strapped to your belly to monitor contractions.
Two other tests may determine your risk of an early delivery:
- Fetal fibronectin. Your doctor will collect vaginal secretions. If the results of testing are negative than you have a less than one-percent risk of delivery within the following two weeks. Dr. Artal points out that this test is not 100 percent accurate.
- Cervical length by vaginal ultrasound. Normally, your cervix is about four centimeters long and shortens before beginning to dilate. If your cervix is shorter, you are at a higher risk for a preterm birth.
How will my doctor treat irritable uterus?
Dehydration, a full bladder, and stress can aggravate an already taxed uterus and lead to contractions. Making simple lifestyle choices could prevent contractions.
Yet women who are experiencing contractions before their 37th week of pregnancy that are causing the cervix to dilate, coupled with a shortening cervix, need to take additional precautions. Your doctor may recommend bed rest, over-the-counter or prescription medications, or even hospitalization if the problem persists.
Lynette Sabin believes that understanding her condition helped her manage later pregnancies better. Sabin went on to have two more children. By taking additional precautions such as slowing down, paying attention to how she felt, and trying to avoid stress (as much as a mother of four can), Sabin didn’t notice as frequent of contractions. If you have any concerns about your pregnancy make sure to discuss them with your OB-GYN or midwife.