Pathological contraction ring is due to:

Ref: Outfit's Text Book of Obstetrics, 7th edition, pg. 404 Explanation:Pathological retraction ring/ Bandl's ring is seen in obstructed Labor.Contraction ring /Schroeder's ring is seen in incoordinate uterine contraction.Causes of obstructed labor:Fault in passage:CPD. contracted pelvisCervical/broad 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! distress/deathCaput & 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.