Uterine activity and symptoms as predictors of preterm labor
Article Abstract:
Since preterm labor is a major cause of preterm delivery, efforts to prevent preterm birth are aimed at diagnosing preterm labor as early as possible so that effective management strategies can be initiated. Labor is generally defined as regular, intense contractions accompanied by progressive changes in the character of the cervix (dilation and thinning). Drugs that arrest labor, tocolytic agents, are more likely to fail if they are given after labor has progressed to its advanced stages, that is, when the cervix has become dilated more than two centimeters and is 80 percent effaced. In some cases, tocolysis is started in patients who have frequent contractions but who are not actually in labor. Since these medications are quite potent, accurate diagnosis is essential. When pregnancy is nearly completed (40 weeks of pregnancy is the normal term), the intensity of the uterine contractions can be used to differentiate true labor from false labor. However, when these contractions occur before the 37th week of pregnancy, a more sensitive method is necessary. Patient-perceived signs and symptoms of labor, such as contractions, discharge, pelvic pressure, backache and menstrual-like cramps, are unreliable and delay diagnosis. The rate of contractions can be measured using a home monitoring device (ambulatory tocodynamometer), which measures, records and transmits patterns of uterine contractions via the telephone to a perinatal nurse. This study included 51 women with a diagnosis of preterm labor verified by monitor tracings and physical exam. The women were divided into four groups on the basis of the reason for evaluation of preterm labor. Preterm labor was diagnosed by monitored uterine activity alone in 12 patients (24 percent), patient-perceived symptoms alone in 12 patients (24 percent), both contractions and symptoms in 22 patients (43 percent), or physical examination at a routine office visit detecting dilation of the cervix in five patients (nine percent). Fewer women in the monitored group delivered early. Therefore, relying on patient-perceived symptoms alone will delay a diagnosis of preterm labor in more than half of the patients. It is concluded that uterine activity is the most sensitive predictor of preterm labor and that women should report any symptoms of labor or uterine contractions, regardless of frequency. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Obstetrics and Gynecology
Subject: Health
ISSN: 0029-7844
Year: 1990
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Uterine activity characteristics in multiple gestations
Article Abstract:
Women carrying more than one fetus are at a particularly high risk for preterm labor. Some studies have shown that the onset of preterm labor is preceded by a marked increase in uterine contraction 24 to 72 hours before labor reaches its advanced stages. However, multiple pregnancies may have higher baseline contraction rate than women carrying only one fetus. To help clarify this issue, 39 twin gestations, 20 triplet gestations and 10 quadruplet pregnancies were studied. Each patient utilized a home monitoring system (ambulatory tocodynamometer), which measured, recorded and transmitted patterns of uterine contractions via the telephone to perinatal nurses trained to interpret the results. In addition, the nurses were available 24 hours a day to assess signs and symptoms of preterm labor. Uterine activity was found to increase slightly 48 hours before the onset of preterm labor and significantly beyond the levels established as baseline 24 hours before the onset of preterm labor. Since the monitoring was able to diagnose preterm labor before other signs of labor appeared (dilation and thinning of the cervix), the pregnancies were prolonged an additional 48 hours. Treatment with tocolytic agents, drugs that aim to arrest labor, had little or no effect on the crescendo of uterine contractions occurring before the onset of preterm labor. A crescendo of activity prior to preterm labor was seen in women carrying more than one fetus and was similar to that found in women with a single-fetus pregnancy. Home monitoring of uterine activity provided information that was useful in making an early preterm labor diagnosis in women carrying more than one fetus. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Obstetrics and Gynecology
Subject: Health
ISSN: 0029-7844
Year: 1990
User Contributions:
Comment about this article or add new information about this topic: