<s>[INST] context: All symptoms are suggestive of severe Ovarian Hyperstimulation Syndrome. History of infeility treatment is the key to diagnosis here. NOTE: OHSS CAN OCCUR WITH PREGNANCY, IN FACT IT IS MORE SEVERE IN PREGNANCY Molar pregnancy usually presents with bleeding in pregnancy, discharge of grape like vesicles and is diagnosed with USG Choriocarcinoma usually presents with irregular bleeding PV following a normal pregnancy or an aboion or a molar pregnancy. Ruptured ectopic pregnancy presents with acute abdominal pain with or without bleeding PV Mild OHSS Abdominal bloating Mild abdominal pain Ovarian size usually < 8 cm Moderate OHSS Moderate abdominal pain Nausea +- vomiting Ultrasound evidence of ascites Ovarian size usually 8 to 12 cm Severe OHSS Clinical ascites (occasionally pleural effusion) Oliguria Hemoconcentration hematocrit (> 45%) Hypoproteinemia Ovarian size usually > 12 cm Critical OHSS Tense ascites or large pleural effusion Hematocrit (> 55%) White cell count > 25000 Oligouria/ anuria Thromboembolism Acute respiratory distress syndrome [/INST] question: A patient of infeility, treated with ovulation induction and ovulation trigger with inj hcg, tests positive for pregnancy on first day of missed period. She comes to emergency with complains of abdominal distension, vomiting and difficulty in breathing on the same day. Blood pressure is 110/60 and PR is 98/min. Most probable cause of her symptoms is? | options: A: Choriocarcinoma B: Molar pregnancy C: Ovarian Hyperstimulation Syndrome D: Ruptured ectopic pregnancy | answer: C </s>