摘要：Objective: Precise determin.tion.of fetal head position.in.labor is a prerequisite for safe in.trumen.al deliveries, an. essen.ial for the assessmen. of labor progress. Recen. studies have cast serious doubts on.the accuracy of the time-hon.red digital vagin.l examin.tion.(DVE) in.comparison.to tran.abdomin.l ultrasoun. scan. (TUS). However, tran.abdomin.l imagin. is techn.cally difficult with a deeply en.aged fetal head in.the secon. stage of labor. We examin.d the accuracy an. time requiremen.s of tran.vagin.l scan. (TVS) in.the secon. stage of labor for determin.tion.of fetal head position. Study design. Sixty laborin. women.in.the secon. stage of labor with a deeply en.aged fetal head were examin.d by experien.ed n.rse midwives an. sen.or residen.s. Fetal head position.was recorded as “ time on.a 12- hour clock." Subsequen.ly, TUS an. TVS were in.epen.en.ly performed by a skilled son.grapher. Accuracy an. time requiremen.s for all 3 examin.tion. were recorded. Results: Fetal head position.could be determin.d in.all cases by TVS, but n.t in.7 cases an. 9 cases by DVE an. TUS, respectively (P < .03; P < .008). A discrepan.y of 60° or more between.the DVE an. TUS or TVS was foun. in.13/60 cases (21.7% ) an. 14/60 cases (23.3% ), respectively. A ≥ 90° discrepan.y was foun. in.9/60 cases (15% ) an. 12/60 cases (20% ), respectively (P <.02 for comparison.of TUS an. TVS). In.5 cases, the digital examin.tion.erron.ously perceived an.occiput posterior position.as occiput an.erior. n. sign.fican. differen.es in.fetal head position.were detected between.TUS an. TVS, when.the examin.tion.was techn.cally feasible. The mean.time (± SD) required for determin.n. fetal head position.was shortest for TVS (8.7 ± 5.8 secon.s) in.comparison.to DVE (22.7 ± 14.6 se-con.s; P < .0001) or TAS (31.7 ± 19.1 secon.s; P < .0001). Con.lusion. Tran.vagin.l son.graphy was the most successful an. accurate method for determin.tion.of fetal head position.in.the secon. stage of labor, an. required