system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following present similar to unruptured ectopic pregnancy
assistant
The correct answer is  Halban's classical traid:

Delay in normal period followed by spotting
Unilateral pelvic pain 
Small Tender adnexal mass.

This triad is similar to that seen in classic ectopic pregnancy.