References
- Hamilton B J, Martin J A, Sutton P D. Centers for Disease Control and Prevention, National Center for Health Statistics. Births: preliminary data for 2003. Nat Vital Stat Rep 2004; 53: 1–18
- Creasy R K, Iams J D. Preterm labor and delivery. Maternal-fetal medicine, R K Creasy, R Resnik. W.B. Saunders Company, Philadelphia, PA 1999; 498–531
- Iams J D, Goldenberg R L, Meis P J, Mermer B M, Moawad A, Das A, Thom E, McNellis D, Cooper R L, Johnson F. The length of the cervix and the risk of spontaneous preterm delivery. N Engl J Med 1996; 334: 567–572
- Berghella V, Daly S F, Tolosa J E, DiVito M M, Chalmers R, Garg N, Bhullar A, Wapner R J. Prediction of preterm delivery with transvaginal ultrasonography of the cervix in patients with high-risk pregnancies: Does cerclage prevent prematurity?. Am J Obstet Gynecol 1999; 181: 809–815
- Beckmann C A, Beckmann C R, Stanziano G J, Bergauer N K, Martin C B. Accuracy of maternal perception of preterm uterine activity. Am J Obstet Gynecol 1996; 174: 672–675
- Hasenburg A, Behrens C, Fallenstein F, Spatling L. Four-channel tocography in uneventful pregnancies: A prospective study in primigravidas and multigravidas. J Soc Gynecol Investig 2001; 8: 48–53
- Moore T R, Iams J D, Creasy R K, Buran K D, Davidson A L. Diurnal and gestational patterns of uterine activity in normal human pregnancy. Obstet Gynecol 1994; 83: 517–523
- Iams J D, Newman R B, Thom E A, Goldenberg R L, Mueller-Heubach E, Moawad A, Sibai B M, Caritis S N, Miodovnik M, Paul R H, et al. Frequency of uterine contractions and the risk of spontaneous preterm delivery. N Engl J Med 2002; 346: 250–255
- Berghella V, Iams J D, Newman R B, MacPherson C, Goldenberg R L, Muellen-Heubach E, et al. Frequency of uterine contractions in asymptomatic pregnant women with or without a short cervix on transvaginal ultrasound scan. Am J Obstet Gynecol 2004; 191: 1253–1256
- Saito M, Kozuma S, Kikuchi A, Sakai M, Fujii T, Unno N, Okai T, Taketani Y. Sonographic assessment of the cervix before, during and after a uterine contraction is effective in predicting the course of labor. Ultrasong Obstet Gynecol 2003; 22: 604–608