A young girl, 23 years old is presented with complaint of abdominal pain, menorrhagia and 18 weeks size mass arising from hypogastrium. The most likely diagnosis is:

Gynecology and obstetrics are twin subjects that deal with the female reproductive system. While obstetrics deals with pregnancy and its associated procedures and complications, gynaecology involves treating women who are not pregnant. Gynecology comprises of both medicine as well as surgical fields.