6O'leary JA,Leonetti HB.Shoulder dystocia:prevention and treatment.Am J Obstet Gynecol,1990,162(1):5
7Riska A,Laine H,Voutilainen P.Estimation of fetal shoulder width by measurement of the humerospinors distance by ultrasound.Ultrasound Obstet Gynecol,1996,7(4):272
8Cohen B,Penning S,Major C,et al.Sonographic prediction of shoulder dystocia in infants of diabetic mothers.Obstet Gynecol,1996,88(1):10
