What Does Borderline In The Pregnancy Test Mean?

Hello I have question hope you can help I was two weeks late for my period was also binge eating feeling very tried and getting cramps in my belly but I have got the coil in so ignored it first week I was late but thought no better send a test off with doctors rather then buying one it would show up better either way then I d settle well it came back borderline I asked what this means and they said they don t know they just get told borderline they don t know what it means but could I send in another urine sample can you tell me what borderline means please