Frequency of uterine contractions doesn't predict preterm birth for twins

Uterine contraction frequency does not predict spontaneous preterm birth occurring before 35 weeks among women pregnant with twins, according to the results of a new study published in the December issue of the American Journal of Obstetrics and Gynecology.

Roger B. Newman, MD, of the Medical University of South Carolina in Charleston, and colleagues compared uterine contraction frequency among 59 women pregnant with twins and 306 women with singleton pregnancies to determine whether contraction frequency predicted preterm births among twin pregnancies. Beginning at 22 to 24 weeks' gestation, women used a home uterine activity monitor to record contractions two or more times per day on two or more days per week and continued doing so until delivery or 37 weeks' gestation.

Mean uterine contraction frequency was higher in twin gestations than singleton pregnancies during the latter half of pregnancy and time of day (between 1,600 and 0359 hours), but the frequency of uterine contractions was not higher among moms who delivered twins at less than 35 weeks' gestation.

Newman RB, Iams JD, Das A, et al. A prospective masked observational study of uterine contraction frequency in twins. Am J Obstet Gynecol. 2006;195:1564-1570.