I'm sorry you're upset but I don't think the receptionist is at fault here. I've moved around quite a bit and at all of the different surgeries I've been at, the receptionist has always given out the blood results - unless it's bad news.
If you'd asked me that, I would have assumed you were asking me what the results were. I think it's a simple misunderstanding, especially if receptionists would normally give out the blood results. I think her response is entirely understandable.
Also, that doesn't sound like a typical receptionist phrase. Every surgery I've been at they've been a real stickler for not interpreting anything, even when it's obvious. It sounds as if that's something that was written down and was intended for you to be passed on to you. I would seriously doubt that she would conjure that phrase up herself.
On a personal note, I really couldn't summon the energy to be worried that other patients waiting in the room overheard that I'd had a hysterectomy. I agree with PP that you sound disproportionately angry about this.
You humiliated the receptionist deliberately in anger and you seem quite pleased about this. I feel sorry for her - in your own words, the own surgery overheard you making her feel silly - and she's now got to sit in front of them all at work and try to stay professional. If she'd been rude, sarcastic or unpleasant to you then fair enough but your reaction was grossly unfair.
Where I do think you have a point however is the layout of the surgery. It's commonplace for receptionists to read out results or messages from doctors - and this makes sense, rather than taking up an appointment for something simple that could just be passed on. While I personally wouldn't have been bothered, and I absolutely maintain what she did was fine in the circumstances, I do accept that some patients cringe at the idea of being overheard. And of course, there may be times when a patient wants to pass sensitive information to the receptionist.
In light of this, my complaint wouldn't have been about the receptionist but the fact that there was nowhere for the information to be passed over privately, without being overheard. That's entirely valid and something I'd be pushing the GP surgery to resolve.
I appreciate you won't agree with my opinion, nor I with yours. Nevertheless I am still sorry you've been upset by the experience and I hope you're feeling a bit better now. I also hope you're recovering OK from your hysterectomy, that's an enormous procedure and really takes its toll emotionally and physically.