Chronic ectopic pregnancy with undetectable serum -hCG level: A rare type of ectopic pregnancy

Ectopic pregnancy is the implantation of embryo and presence of gestational sac outside of the uterine cavity. Chronic ectopic pregnancy is a rare form of tubal pregnancy frequently presented with a pelvic mass and minimal symptom with a low or absence of beta-human chorionic gonadotropin (β-hCG) titer. Preoperative diagnosis is difficult because of high incidence of negative pregnancy test, nonspecific symptoms and low sensitivity of ultrasonograpic findings. Therefore many cases are diagnosed after surgical exploration. It is characterized by degenerated trophoblastic tissue and chronic inflammatory mass formation in the fallopian tube. In this current case report we present a 24-year-old nulliparous woman admitted to our emergency department because of lower abdominal pain. Ultrasonography showed a mass of 4 cm in size in left adnexal area. On color Doppler ultrasound, mass showed no vascularity. Serum β-hCG level was undetectable which in the sense of less than 10 IU/ ml. Laparoscopy revealed a left tubal ampullary mass consistent with an old tubal ectopic pregnancy. Laparoscopic left salpingectomy was performed. Histopathological examination confirmed chronic ectopic pregnancy. In conclusion, even if serum β-hCG level is less than lower reference limit and clinical symptoms are disguised, ectopic pregnancy should be considered in the differential diagnosis of adnexal masses in reproductive aged women.