Uterine Contraction Monitoring, Maintenance Tocolysis, and Preterm Birth

Uterine contractions occur in runs of 1-3/hr throughout pregnancy from early in the second trimester until full term usually without consequence. Regular uterine contractions are essential in every case of preterm labor (PTL) resulting in preterm delivery at <37 weeks. It has been demonstrated that women are unable to accurately perceive the contractions associated with preterm labor while uterine contraction monitoring can frequently detect these contractions at an early enough time that acute tocolysis can stop preterm labor in most cases and significantly prolong the pregnancy. In women who have cervical shortening, those who have preterm labor symptomatology with multifetal gestations, or patients who have already had an episode of preterm labor, uterine contraction monitoring has been helpful in prolonging the pregnancy by early detection. As an example, women, after receiving tocolysis for true preterm labor, are monitored (tertiary prevention) in the home (whether or not they are receiving maintenance tocolytics) and when a second episode of PTL occurs, the majority reach the hospital for appropriate treatment before excessive cervical dilatation has occurred. Alternatively, following successful acute tocolysis in the hospital, patients may receive maintenance tocolysis with a subcutaneous terbutaline infusion pump and are also managed at home with continued contraction assessment. This chapter will review the available literature regarding the use of contraction monitoring for tertiary prevention as well as subcutaneous terbutaline maintenance therapy for treatment of contractions.