Uterine Relaxants
UTERINE RELAXANTS Many risk factors are associated with the triggering of premature labor, that is, labor that begins before the end of week 37 of gestation. These include maternal smoking or drug abuse, lack of prenatal care, multiple gestation, placental abnormalities, infection of the fetal membranes, cervical incompetence, and previous preterm birth. Although most episodes are of unknown origin, premature labor can develop spontaneously or may follow early rupture of fetal membranes, perhaps as a result of a genetically associated abnormality. Uterine relaxants ( tocolytic drugs ) are administered where prolonged intrauterine life would greatly benefit the fetus or would permit additional time to allow treat-ment with drugs such as corticosteroids, which promote the production of fetal lung surfactant. Tocolytics are also used when temporary uterine relaxation is be de-sirable (e.g., intrauterine fetal resuscitation). While hy-dration, bed rest, and sedation have been used to