<prompt> Vaginal delivery can be allowed in all except aEURMonochrionic, monoamniotic twinsMentoanteriorExtended breechDichorionic twins with first veex second breech  <response>: Monochorionic, monoamniotic twins Ref: Williams Obstetrics 23e, Chap. 24 and 39; Danfroths Obs. and Gynae 10e Chap 14 22; Dutta Obstetrics 6e, p 209. Mentoanterior face presentation, extended breech and dichorionic twins with first veex and second breech, all of these can be allowed for vagina delivery. Monochorionic monoamniotic twins are best delivered by caeserean section as soon as lung maturity is attained for fear of entanglement and tightening of umbilical cord which may lead to fetal distress and death. Monoamniotic twins are rare, complicating 1 of monozygotic twins. They have a very high fetal moality rate of 40. Besides cord entanglement these twins are at greater risk of congenital anomalies, conjoining, preterm bih and twin-twin transfusion syndrome TTTS. Lets have a revision of twinning: Mode of delivery of twin pregnancy After the first twin is delivered vaginally, some norms are to be followed for delivery of second twin as depicted in thefollowing flowcha- ECV - External cephalic version, CPD - Cephalopelvic dispropoion. NVD - Normal vaginal delivery, IPV - Internal podalic version Unskilled in IPV. breech extraction and assisted breech delivery. Now lets have a look at mode of delivery for malpresetztations - ACOG - American College of Obstetrician and Gynecologists - 2006 guidelines Occipito posterior position is not dealt here as it is a malposition not rnalpresentation. 