I had a unprotected sex last month with my gf but I didn't cum inside her. She has missed her periods it's now more than 45 days without periods. She is saying she has done pregnancy test at home thrice but it showing negative. I don't trust those tests I want to get her checked at a clinic please suggest me which is the best and cost effective test to be 100% sure about pregnancy results. My gf is saying she missed periods maybe because of PCOS which she is developing. Please suggest suitable and cost effective test.