Intrapartum Translabial Ultrasound (ITU) to Assess Birth Progress

Abstract

For many years, diagnostic ultrasound has had a place in the labor ward. Recently, it has also been applied to assess birth progress. Initially, the position of the fetal spine and occiput was assessed by transabdominal ultrasound and correlated with vaginal palpation to improve the detection of OP presentation. From 2005, translabial ultrasound was used, initially before (Dietz and Lanzarone, Ultrasound Obstet Gynecol 25:165–168, 2005; Dietz et al. Ultrasound Obstet Gynecol 27:409–415, 2006) but then also during labor (Dietz and Lanzarone, Ultrasound Obstet Gynecol 25:165–168, 2005; Dietz et al. Ultrasound Obstet Gynecol 27:409–415, 2006; Fuchs et al. Ultrasound Obstet Gynecol. 31:484–486, 2008; Henrich et al. Ultrasound Obstet Gynecol 28:753–760, 2006; Tutschek et al. BJOG 118:62–69, 2011; Barbera et al. Ultrasound Obstet Gynecol 33:313–319, 2009; Ghi et al. Ultrasound Obstet Gynecol 33:331–336, 2009; Kalache et al. Ultrasound Obstet Gynecol 33:326–330, 2009) to measure head station objectively. Studies of accuracy of vaginal palpation, measured using a phantom, showed that obstetric vaginal palpation is very operator dependent and, overall, not accurate; this applies to palpated head stations expressed in centimeters above or below the mid-pelvis and simply as “high,” “mid,” and “low,” according to the ACOG classification (Dupuis et al. Eur J Obstet Gynecol Reprod Biol 123:193–197, 2005).