I’m a HCP and often have to ask this question.
I usually start by asking about the patients LMP. Then I’ll ask if there’s any chance of pregnancy, and then based on the persons answer I’ll adjust my next question.
If it’s a flat “no”, then I’ll say “has there been any unprotected sexual intercourse?”.
The patients answers inform my questions and my assessment of the risk.
Sometimes people will say “Yes, there has been UPSI, but I don’t think I’m pregnant” and we’ll explore that further. As of course there is a pregnancy risk, and unless they’ve had a negative Urine HCG since the first day of missed period then they could definitely be pregnant.
Sometimes they say “No, I’m on the depo/implant/coil” and I’d usually take that as a reliable “not pregnant”. But if they happen to be calling about a unilateral abdominal pain and PV bleeding (without signs or symptoms indicating another differential diagnosis) then we’d probably need to explore further, as of course people can very rarely still get pregnant on these forms of contraception, and particularly on the coil the risk of ectopic is increased.
Basically, what I’m saying is it depends on the individual circumstances and the answers the patient provides. But it’s safest to assume that anyone between the ages of 12 and 55 is pregnant until proven otherwise, if there is any uncertainty about LMP/Contraception/UPSI.