As student nurses, we pick one of our second-year placements and are advised to go into an area that interests us most. I chose to do a five-week stint in a sexual health clinic. Sexual health clinics are magical places where surprises spring from the walls. I once walked into work to find an aggressive looking – but lovely – nurse loudly spelling the word “gonorrhoea” down the phone while slurping white hot chocolate from a mug with the c-word on it. All before 7.30am.

I made particular friends with a doctor – we’ll call him Dr Ray. He was a genial Nigerian man who possessed the sense of abandon that could only arise from being a married religious professional who has seen more vaginas than Charlemagne. Dr Ray asked me to lead a couple of his appointments; he had a ton of paperwork to get through and was faced with getting it done or actually seeing his patients (thank you NHS management). He suggests an apparent win-win situation: we both sit in the consulting room, I leading the appointments and he sitting in the corner, quietly knuckling down to his paperwork but on hand should I need him.

I am chuffed – I’m still a student, I’ve never run a clinic before and it’s great experience. We carefully select my first ever patient, paying particular attention to the age and gender. She’s middle-aged, which would suggest she’s unlikely to have anything particularly unusual going on. Pompously, I walk into the waiting room and call her name. As she gets up and walks over, I notice a peculiar gait: “Thrush” I think, “She’s clearly got a really nasty bout of thrush.” Other than the hobble, she looks entirely normal.

Once in the room, I explain who I am, who Dr Ray is, and how we will go about things. I ask her about her sexual history, whether she has children etc. She tells me in a clipped accent that she’s been married for 20 years and has young children. She hasn’t slept with anybody else since getting married. “Thrush!” I smugly congratulate myself. “Irrefutably thrush.”

“So what brings you here today, Mrs T?” I ask, demurely. “Well” she begins, shifting her position and wincing, “I was playing with my son’s dinosaur, and it’s stuck.”

“OK, Mrs T, but why are you in the sexual health clinic today?” I continue, somewhat bemused.

“It’s stuck,” she repeats, giving me a pointed look.

There is a long pause, the penny’s still in the air for me, but I can see the outline of Dr Ray’s shoulders silently heaving as he contains his giggles.

“I’m still not quite with you. Can you elaborate on that please?” I ask.

“It’s a T-Rex,” she adds. She gestures helplessly towards her crotch and looks stricken. “It’s stuck.” The penny finally drops.

I am overwhelmed with a range of questions but, understandably, lost for words. At this point Dr Ray interjects and suggests we get our patient on to the couch. Speculum in, we come face to face with Rex, who is poised for battle with my forceps, claws up, as it were. There is a part of the female anatomy called the posterior fornix, a little trench, right up by the cervix – “whose anatomical purposes, among others, include pooling sperm” I think to myself. This poor little fornix had pooled a 5cm tall toy T-Rex (made in China). Rexy had managed to get lodged so when looking toward the cervix using a speculum you could just see his head and front claws above this anatomical parapet.

After some deft manoeuvring with the forceps and a prophylactic course of antibiotics, the offending item was deposited in the medical waste bin. One of the best sentences I have ever uttered as a nurse, scratch that, one of the best sentences I’ve ever said, is: “I don’t advise inserting children’s toys during sexual activity, however if you do choose to masturbate with a toy dinosaur, I recommend buying your own, and perhaps putting it in a condom, or tying a leash to its foot.”

The lady nods appreciatively and hobbles off. Dr Ray and I wait in silence, poised until she’s safely out of earshot, before we both break down with laughter. It took every ounce of my strength to remain professional that day, and I learned never to pre-empt patients or their conditions again.

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• The writer writes under a pseudonym