References
- Ayers J WT, Degrood RM, Compton AA, Barclay M, Ansbacher R. Sonographic evaluation of cervical length in pregnancy: diagnosis and management of preterm cervical effacement in patients at risk for premature delivery. Obstet Gynecol 1988; 71: 939–44
- Paterson-Brown S, Fisk NM, Edmunds DK, Rodeck CH. Preinduction cervical assessment by Bishop's score and transvaginal ultrasound. Eur J Obstet Gynecol Reprod Biol 1991; 40: 17–23
- Gomez R, Galasso M, Romero R, et al. Ultrasonic examination of the uterine cervix is better than cervical digital examination as a predictor of the likelihood of premature delivery in patients with preterm labour and intact membranes. Am J Obstet Gynecol 1994; 171: 956–64
- Hilpert PL, Kurtz AB. The role of transvaginal ultrasound in the second and third trimesters. Semin Ultrasound CT MR 1990; 11: 59–70
- Varma TR, Patel RH, Pillai U. Ultrasonic assessment of cervix in ‘at risk’ patients. Acta Obstet Gynecol Scand 1986; 65: 147–52
- Kushnir O, Vigil DA, Izquierdo L, Schiff M, Curet L. Vaginal ultrasonographic assessment of cervical length changes during normal pregnancy. Am J Obstet Gynecol 1990; 162: 991–3
- Murakawa H, Utumi T, Hasgawa I, Tanaka K, Fuzimori R. Evaluation of preterm delivery by transvaginal ultrasonographic measurement of cervical length. Obstet Gynecol 1993; 82: 829–32
- Zorzoli A, Soliani A, Perra M, Caravelli E, Galimberti A, Nicolini U. Cervical changes throughout pregnancy as assessed bs transvaginal sonography. Obstet Gynecol 1994; 84: 960–4
- Anderson HF., Nugent CE., Wanty SD, Hayashi RH. Prediction of risk for preterm delivery by ultrasonographic measurement of cervical length. Am J Obstet Gynecol 1990; 163: 859–67