This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Obstetrics, Subject name: Gynaecology & Obstetrics
In which of the following conditions a medical treatment of ectopic pregnancy contraindicated? 
Select and explain. 
A. Sac size is 3 cm, B. 50 mL free fluid in pelvis, C. Presence of foetal hea activity, D. Previous ectopic pregnancy
C: Presence of foetal hea activity
Answer: C: Presence of foetal hea activity 
Explanation: Medical management (methotrexate) is the treatment of choice for an ectopic pregnancy whenever the required criteria are fulfilled- Patient should be hemodynamically stable (unruptured tubal ectopic pregnancy). Foetal cardiac activity absent (presence of cardiac activity is a relative contraindication). b-hCG levels <5,000 mIU/mL (levels > 5,000 micro IU/mL is a relative contraindication). Gestational sac diameter <4 cm. Free fluid in POD <100 mL.