Table 1 Studies evaluating accuracy of transvaginal digital examination compared to ultrasound in diagnosing the position of the fetal head in labour
Author, citation | Study design | Exposures | Outcome measures | Results | Conclusions |
|---|---|---|---|---|---|
Akmal S et al. J Matern-Fetal Neo M 2002, 12(3): 172-7 | Prospective study 496 women in labour (1st & 2nd stages) | DVE vs TAS (gold standard) | Agreement of DVE within ±45° of TAS correct | DVE in agreement with TAS in 163 cases (49.9%) | Digital examination inaccurate in 50% of cases |
Souka AP et al. J Matern-Fetal Neo M 2003; 139(1): 59- 63 | Prospective study 148 women in labour (1st & 2nd stages) | DVE vs TAS (gold standard) | Agreement of DVE within ±45° of TAS correct | Accuracy of DVE 31.3% in 1st stage & 65.7% in 2nd stage, more likely to be inaccurate in OP position | Digital examination is less accurate than ultrasound, especially in OP position. |
Sherer DM et al. Ultrasound Obst Gyn 2002; 19(3): 258-63 | Prospective study 102 women in labour (1st stage) | DVE vs TAS (gold standard) | DVE accurate in 24 cases (24%) | High error rate (76%) with digital examination | |
Sherer DM et al. Ultrasound Obst Gyn 2002; 19(3): 264- 8 | Prospective study 112 women in labour (2nd stage) | DVE vs TAS (gold standard) | Absolute error when DVE not consistent with TAS; and inconsistency of >45° | Absolute error of DVE 65% DVE incorrect by > 45° in 44 cases (39%) | Ultrasound improves accuracy |
Dupuis O et al. Eur J Obstet Gynecol Reprod Biol 2005; 123(2): 193-7 | Prospective study 110 women in labour (2nd stage) | DVE vs TAS (gold standard) | Agreement of DVE within ±45° of TAS correct | In 20% of the cases, DVE differed significantly (>45°) from TAS, higher in OP & OT positions | Transabdominal ultrasound can increase accuracy |
Kreiser D et al. J Matern-Fetal Neo M 2001; 10(40): 283-6 | Prospective study 44 women in labour (2nd stage) | DVE vs TAS (gold standard) | DVE & TAS findings compared to actual fetal head position at delivery and restitution of the fetal head – if different, considered to be wrong and quantified as =90°, <90° or >90° | TAS less error than DVE: 6.8% vs 29.6%, p = 0.011 | TAS is more accurate |
Zahalka N et al. AJOG 2005; 193(2): 381-6 | Prospective study 60 women in labour (2nd stage) | DVE vs TAS vs TVS | Agreement of DVE within 60° of TAS correct | Discrepancy between DVE & TAS 21.7% Discrepancy between DVE & TVS 23.3% 5 cases where DVE erroneously diagnosed position as being OA when it was OP | TAS and TVS more accurate than transvaginal digital examination |
Chou R et al. AJOG 2004; 191: 521- 4 | Prospective study 88 women in labour (2nd stage) | DVE vs TAS | DVE & TAS findings compared to actual fetal head position at delivery (direct visualisation of position at vaginal delivery after spontaneous restitution of the head or at caesarean section). Considered correct if DVE/TAS within 45° of actual position. | Accuracy of DVE 71.6% vs 92% accuracy for TAS, p = 0.018 | TAS more accurate than DVE |
Rozenberg P et al. Ultrasound Obst Gyn 2008; 31(3):332 - 7 | Prospective study One novice doing both TAS and VE 100 women (≥ 7 cm dilated) | DVE vs TAS | Learning curve of a novice at diagnosis of the fetal head position by DVE & TAS compared to an expert | Error rate of DVE 50% over first 50cases, down to 28% over last cases vs 8% error with TAS | Learning and accuracy of diagnosis of the fetal head position easier & higher with TAS |
Akmal S et al. Ultrasound Obst Gyn 2003; 21(5):437-40 | Prospective study 64 women undergoing instrumental delivery | DVE vs TAS | Agreement of DVE within ±45° of TAS correct | Error rate of DVE 26.6% (17 cases), igher for OP and OT | DVE inaccurate in a quarter of cases before instrumental delivery |
Wong GY et al. | RCT 40 women undergoing vacuum extraction | DVE vs TAS | Accuracy of vacuum cup placement with respect to the flexion point | Mean distance between chignon & flexion point: 2.1 ± 1.3 cm in DVE + TAS group vs 2.8 cm ± 1.0 cm in VE group (p = 0.039) | TAS improves vacuum cup placement |