<prompt> Pathological contraction ring is due to:Obstructed labourUterine inertiaPreterm labourOligohydramnios  <response>: Ref: Outfits Text Book of Obstetrics, 7th edition, pg. 404 Explanation:Pathological retraction ring Bandls ring is seen in obstructed Labor.Contraction ring Schroeders ring is seen in incoordinate uterine contraction.Causes of obstructed labor:Fault in passage:CPD. contracted pelvisCervicalbroad ligament fibroidImpacted ovarian tumourFault in passenger:1 ransverse lieBrow1 presentationCongenital malformationslike hydrocephalus, fetal ascites, double monstersMacrosomic babyLocked twinsSalient clinical features:Band Ps ringTonic upper segment and distended thinned out lower segmentBlood stained urineFeta! distressdeathCaput 3rd degree mouldingFailure of descent of the presenting partComplications:Maternal:Metabolic acidosisGenital sepsisPPH shockVesico vagi n al tl st u 1 aSecondary amenorrheaFetal:Asphyxia, acidosisIntracranial hemorrhageInfectionManagement: caesarean sectionCause of vesico vaginal fistula in obstructed labor: Pressure necrosis of the base of the bladder between pubic symphysis and fetal bead. 