The rate of vaginal delivery , term pregnancy and neonatal weight of 31 % ( 10/32 ) , 91 % ( 29/32 ) and ( 3 214 306 ) g in sildenafil group were different with 19 % ( 6/32 ) , 84 % ( 27/32 ) and ( 3 004 458 ) g in control group ( P < 0.05 ) .