<prompt> Atonic uterus contraction seen in all EXCEPTMultiparityIUGRPolyhydramniosProlonged labour  <response>: IUGR: 213, 410-11- Dutta 7th editionAtonicity of the uterus is the commonest cause of post partum haemorrhage 80Causes of PPH Atonic Uterus 80 Traumatic 20- Grand multipara Retained tissues Bits of placenta, blood clots causes PPH due to imperfect uterine retraction- Over distension of the uterus- Malnutrition and anaemia- APH Drugs - tocolytic drugs ritodrine MgSO4, Nifedipine- Prolonged labour- Anaesthesia Blood coagulation disorders - are abruptio placetae, Jaundice in pregnancy, Thrombo cytopenic purpura, HELLP syndrome or in IUD- Indication or augmentation of delivery by oxytocin- Malformation of the uterus- Uterine fibroid- Mismanaged third stage of labour- Placenta accreta, percreta constriction ring uterus- Precipitate labourPPH is due to uterine atony during labour in polyhydromnios 213-Dutta 7 