A 32 year old woamn with two live children was brought to emergency with the history of missed period for 15 dyas, spotting since 7 days and pain abdomen since 6hrs. Her pulse was 120/min, pallor ++, systolic BP BOmmHg. There was fullness and ternderness on per abdomen examination. Cu-T thread was seen through external os on P/S examination On PN examination, cervical movements were tender, uterus was bulky and soft. There was fullness in pouch of Douglas. She is most likely suffering from :