Medical Fun Facts Episode 69: The microbiology of a popular sexual position

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Tonight, I’m going to do my best to use medical language rather than colloquial phrases and terms. That said, some may creep in. We're at episode 69. The number 69, has a significant place in modern popular culture. For those who don’t know what I’m talking about and if you’re conservatively minded, you may not want to listen further. If you have children listening who haven’t had their home and school sexual education sessions yet, you may want them to listen in if they’re not familiar with oral sex and human health.

Gargling to prevent gonorrhoea

In December 2016, I pinned to the show’s Facebook page, a status update that refers to an article written by some Australian sexual health practitioners who wrote about the potential benefits of using a commercially available antiseptic throat gargle to prevent oral gonorrhoea.

Diagnosing oropharyngeal STIs unlike genital STIs is not as straight forward as you may expect. It’s not as simple as collecting a swab and growing the gonococcus or detecting chlamydia nucleic acid by PCR.

Before I forget, we shouldn’t ignore anorectal infection either, although in the context of 69, anal action takes a little more effort. It depends on how far posteriorly you want to go with your head and anatomically flex your neck rather than extend it.

Cunnilingus and fellatio

So back to cunnilingus and fellatio and I suppose we should mention rimming and felshing too. The article from December 2016 written by some sexual health practitioners in Melbourne describes how the authors recruited patients with pharyngeal gonorrhoea and asked one group to gargle with a commercial antiseptic mouthwash while the other group gargled saline. Swabs were collected before and after the gargling. The result was that the gargling of an antiseptic solution reduced the number of gonococci cultured. The authors speculated that regular use may have a role in infection prevention. Now before we get too excited, this is not the most robust of studies and it came out just before Christmas 2016 I think in an effort to get people to think about STIs during the party season. It is an intriguing notion though but no assumptions should be made about reducing numbers of other sexually transmitted microorganisms like Chlamydia trachomatis and Human papilloma virus.

So, I mentioned earlier that diagnosis in nongenital specimens isn’t straightforward. Laboratory diagnosis from a man’s urethra is generally easy if infection is present because there are not many other bacteria present in the urethra and a man’s urethra is relatively easy to sample. We can ask a man to provide a first void urine specimen or we can insert a swab into his urethra and collect a specimen that way. We can also do this with a women’s urethra but it is not as simple and because the female urethral opening is contiguous with the vulva, female genital tract flora, including enteric flora is not uncommon to find especially in swab specimens.

Now as a side note, some men are into the practice of sounding, where they or a partner insert stainless steel sounds into their urethra for sexual pleasure. While the sounds are smooth and lubricant may be used, mucosal trauma may occur and this can increase the risk of infection of the mucosal lining of the urethra. I suppose sounding could extend to inserting the spherical portions of a tongue piercing into a partner’s urethral meatus too.

Specimens from the genital cervix, rectum and oropharynx all have significant amounts of commensal flora which can make culture of the gonococcus a little more challenging even with selective agar. In rectal and oropharyngeal specimens, we can employ techniques like polymerase chain reaction (PCR), however, the commercially available in vitro diagnostic devices are not readily validated for those sites. You will see reports from many pathologists which have disclaimers when reporting the detection of gonococcus or chlamydia from rectal and oropharyngeal specimens.

A mouthful of what?

Alas, there are many other microorganisms we need to be concerned about and while some diagnostic tests exist, not all of them are readily available and performed unless specifically requested. For example, when you cunnilingue or fellate (I’m guessing these are the verbs of cunnilingus and fellatio respectively), you may want to think about what is entering your mouth. For that matter when you’re rimming and felshing, you should also think about what’s going in your mouth in the context of the very small market garden otherwise known as the microbial flora of your partner’s sexual orifices. This is why condoms and dental dams are well described in sexual education literature, that said, I’m aware of the ick factor associated with sucking on or through latex covered in spermicide and virucide. Just imagine getting a mouthful of Trichomonas vaginalis as it wiggles and jiggles and tickles inside you, or Human papilloma virus which has the potential to cause a malignancy in your throat. Or the yeasty goodness of thrush which may have the consistency of cottage cheese. If you smell rotting fish you may be faced with bacterial vaginosis.

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Medical Fun Facts Episode 69 | The microbiology of this sexual position

Medical Fun Facts Episode 69 | The microbiology of this sexual position

Fortunately, former Australian of the Year with a heavy Scottish accent, Prof. Ian Frazer has paved the way with his HPV immunisation, and we will see dramatic declines in HPV associated malignancies especially if boys get immunised as well as girls.

Now this isn’t meant to put you off oral sexual activity, but you can take precautions and it is helpful for partners to have regular sexual health checks.

Felshing (Felching) and Rimming

Then there is felshing and rimming. Felshing is sucking semen out of an orifice, usually a vagina or anus. Remember pathogens can live happily in semen, so before you felsh you may want to be sure your partner doesn’t have any STIs. If we consider felshing and rimming together, apart from STIs there are also causes of enteric infection that can be transmitted via the faecal-oral route (that’s r-o-u-t-e for my Australian audience, also root, that is r-o-o-t could be applicable here too if you want to extend the definition to sexual contact in the broad). Hepatitis A viral infection as well as the usual things like salmonellosis can be transmitted via felshing and rimming. “What about if I only felsh vaginas?” I hear you ask. Well just remember, it’s not uncommon to find enteric flora intermingling with vaginal flora.

Monty Python

Should I stop here? One of my favourite comedic groups is Monty Python. I suggest you go to a search engine and enter “Monty Python Medical Love Song Lyrics”. You can also search for “Monty Python Penis Song”, that’s another classic. Then most relevant to this show go and look for “Monty Python Sit on my face”.

So, let’s summarise episode 69 of Medical Fun Facts. The sexual position that places an emphasis on orogenital and oroanal stimulation may well be very popular and without wanting to conflate this with an Oedipal complex, when you’re cunnilinguing, fellating, felshing and rimming, remember what your Mum said about putting things in your mouth. Make sure they’re clean.

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