Comparison of effects of digital vaginal examination with transperineal ultrasound during labor on pain and anxiety levels: a randomized controlled trial

Objective To evaluate whether routine vaginal examination during labor is associated with increased levels of anxiety and pain compared with transperineal ultrasound assessment. Methods This was a single-blinded, parallel, randomized controlled trial conducted in a tertiary care facility. Parous pregnant women without a known psychiatric condition who were seen at the care facility between November 2015 and March 2016 were included in the trial. Participants had an uneventful pregnancy and were assigned randomly to routine digital vaginal examination or transperineal ultrasound assessment during labor. Psychological distress levels, measured by the Symptom Checklist-90-Revised, and anxiety levels, measured by State-Trait Anxiety Inventory (STAI), were recorded before admission, and pain, measured using a visual analog scale, and anxiety were recorded during the latent phase of labor, the beginning of active labor and the postpartum period. A sample size of 45 women per group (n = 90) was planned to compare methods of assessment. Results Ninety women were randomized (1: 1 allocation) to one or other of the interventions. Preadmission psychological distress and anxiety levels were similar between the two groups (P = 0.93 and 0.65, respectively). Most of the studied characteristics were similar in each group including duration of labor, number of examinations, analgesic administration during labor, episiotomy rate and interval between deliveries. Visual analog scale scores revealed that pain perception was reduced during latent (mean difference, -1.5 (95% CI, -2.51 to -0.57); P < 0.01) and active (mean difference, -1.2 (95% CI, -2.45 to -0.09); P = 0.03) stages of labor and during the postpartum period (mean difference, -0.5 (95% CI, -1.02 to -0.06); P = 0.02) in participants who had a transperineal ultrasound assessment compared with participants who had a digital vaginal examination. STAI scores revealed that anxiety levels were similar between the two groups during the latent and active phases of labor and during the postpartum period (P = 0.07, P = 0.38 and P = 0.13, respectively). Conclusions The perception of pain was significantly reduced with the use of a transperineal ultrasound assessment compared with routine digital vaginal examination. However, only during the latent stage of labor was the magnitude of the observed effect sufficiently great to be considered clinically significant. Our results indicate that transperineal ultrasound assessment could be preferred to digital examination for the evaluation of progression of labor during this phase. Digital examination has no clinically relevant effects on state anxiety levels, as measured by the STAI. Copyright (C) 2016 ISUOG. Published by John Wiley & Sons Ltd.