Uterine activity during pregnancy in ambulatory patients: comparison of singleton and twin gestations

Prelabor uterine activity was monitored daily in a group of ambulatory outpatients who were delivered at term. The study included 22 patients with one fetus and 18 with twin gestations. The mean weekly frequency of uterine activity during twin gestations was found to be significantly higher throughout pregnancy than that identified during pregnancies with a single fetus. In twin gestations a gradual significant rise in frequency of contractions could be observed with advancing gestational age. The data presented could help establish the guidelines for evaluation of uterine activity records during pregnancies complicated by a multifetal gestation.