For those seeking the full carnal experience out there, my advice is - don't. There are loads of reasons why one should stick to what drives us to making love with someone in the first place, such as the ambience and the spiritual connection with the person we are doing this with. However, this is merely my preference. A lot others prefer the physical performance, where sexual intercourse is an exhibition of one's stamina and strength. For some of my friends, this is even a competition - where girls are reduced to a mere number and dinner tables are littered with pride-fuelled conversations about their recent conquests. My focus here is none of these things, since delving into an elaborate sociological discussion is just going to send people to sleep. I focus on a rare condition called brain aneurysms.
The classical story goes like this: Tigger was 25 years old and had finally acquiesced to his girlfriend's demands to have sex. He was never keen on the idea, since he never knew what to do during those moments of intimacy. When his girlfriend pulled down his boxers and performed fellatio on him, he instantly experienced an intense physiological response. By the time he reached orgasm, he suffered from multiple bouts of severe headaches. They were followed by a lapse into unconsciousness. His girlfriend called the emergency services and he was sent to the hospital. A few hours later, he was pronounced dead due to cerebral aneurysmal rupture.*
This scenario may seem outlandish, it has been published in multiple case reports [1] [2]. However, how can this happen? Surely there are some warning signs? Moreover, what is meant by cerebral (brain) aneurysms and are they dangerous?
Aneurysms are one of the more dangerous types of brain disease. They concern the blood vessels. More specifically, the arteries. With the weakening of a section of the vessel wall, that section is unable to push blood forward effectively by constricting. It thus 'balloons' out upon the arrival of blood. More specifically, there are three layers of the vessel wall (in very simplistic terms), which are: (a) tunica adventitia (the outermost), (b) tunica media (middle), and (c) tunica intima (the innermost). (a) and (b) are separated by the external elastic lamina. (b) and (c) are separated by the internal elastic lamina. It has been shown in research that cerebral aneurysms are caused by gross weakening of (b) and the reduction of the internal elastic lamina. [3] For our purposes, in cerebral arteries, the tunica media contains mostly smooth muscle fibres and elastic tissue, crucial for constriction. [4] No wonder there is a high risk of 'ballooning' when it doesn't work well.
[5]; as seen in the diagram above, the outpouching is situated at the branching of an artery.
However, what leads to the weakening of the arterial walls? We don't know. There is a wide range of pathologies behind the formation of brain aneurysms. American Stroke Association states that most aneurysms arise at the age of 40 or beyond [5], but genetics also play a part. A study says that when 1-2 family members develop intracranial aneurysms (i.e. aneurysms within the skull), there is a 9.8% risk for their first-degree relatives (e.g. biological children, siblings) to be afflicted by this condition, at > 30 years old. [6] In terms of processes, blood vessel weakening can be due to natural ageing (although the extent and severity depend on different individuals), previous autoimmune disease and arterial dissection. [5] Infections such as tuberculosis can also cause aneurysms (they are called 'mycotic aneurysms'). [7]
Such aneurysms can grow really big, big to the extent that the outpouching cannot take it anymore. The wall gets thinner and thinner. Eventually, boom! The aneurysm bursts and haemorrhage in the brain ensues. This bleeding can lead to catastrophic consequences, including the constriction of the local vessels (thus leading to inadequate blood supply to neighbouring brain structures) and hydrocephalus (too much fluid in the brain). There is a rapid increase in intracranial pressure (ICP), leading to a rapid decrease in perfusion pressure. Perfusion pressure is the blood pressure required to pump blood to the brain. Once the intracranial pressure reaches a point where the perfusion pressure drops below 25 mmHg, the brain fails to function and the patient drops to unconsciousness. Death is the eventuality without proper treatment. [8] Since this bleeding occurs below the arachnoid mater (refer to the diagram above), the middle layer of the three outer coverings of the brain, it is called Subarachnoid Haemorrhage (or SAH, for short).
Having sexual intercourse comes with a big issue - it's not only about the rubbing of the genitalia. It's about getting the orgasm. Orgasm is the intense physiological response that comes during sexual intercourse. Many parts of our body change during this literally life-transforming activity. For both boys and girls, the sex organs enlarge due to the influx of blood (boys = the penile shaft, girls = the clitoris). This can be traced to the relaxation of blood vessels. Hormones are released, with the most famous one 'oxytocin', known as the 'cuddling hormone' which makes one feel more attached to one's partner. We breathe more quickly. Our heart rate and blood pressure rise. [9] At the height of ecstasy (not an exaggeration - there is literally stimulation of the so-called 'reward pathway' in our brain, leading to the ecstatic feeling we experience), if the patient already has an aneurysm, this increase in blood pressure is the final straw. Blood pounding through the arteries, the friction (or to be geekier, the vascular shear stress) between the blood and the wall increases. Whenever I think of friction, I think of Thomas the Tank Engine pounding the tracks on the Island of Sodor. Just before train accidents (seems to be the common theme in those cartoons), sparks emerge as the engine pulls the brakes. A similar phenomenon happens in blood vessels. Injuries result in the weakened vessel wall until it breaks down. A gap is formed and, like water leaking from a dam, blood flows out of the vessel.
What about the warning signs? Well, sometimes present, sometimes absent. Sometimes, patients might feel headaches from time to time. Others exhibit what we call 'cranial nerve palsies', i.e. any of the 12 nerves originating from the brain to the head and neck (with one of them going across the entire body) not working well. They might have problems adjusting to bright conditions, or move their face. In fact, all depend on the size and location of the aneurysm. [10] It follows that a larger aneurysm, located in a more tortuous vessel (i.e. a vessel that snakes across the terrain, with more turns and bends) is more prone to rupture. It is definitely possible not to know if you have an aneurysm or not. Family history may shed a clue but nothing else- in fact, the horrors of sudden aneurysmal rupture are exhibited by the death of Chris Miles, a fictional character in Series 2 of Skins. The aneurysm ruptured twice.
Not trying to scare anyone, but next time when anyone is thinking of going for a 'mind-blowing' sexual experience, be careful what you wish for.
* Actually, there are different types of cerebral aneurysms out there. They can be categorised according to morphology, location and size. In the brain, we are most concerned with aneurysms in four places: basilar artery (very high mortality), internal carotid artery, middle cerebral artery, anterior communicating artery.
[1] Braun C, Ricklin M, Pauli A, Ott D, Exadaktylos A, & Pfortmueller C. (2015). Death after Sexual Intercourse. Case Reports In Emergency Medicine, 2015, 1-4. https://doi.org/10.1155/2015/646438
This is a case of a 22-year old female patient who experienced basilar aneurysmal rupture during sexual intercourse.
[2] Portunato, Landolfa MC, Botto M, Bonsignore A, De Stefano F, Ventura F. Fatal subarachnoid hemorrhage during sexual activity: a case report. Am J Forensic Med Pathol. 2012 Mar;33(1):90-2. doi: 10.1097/PAF.0b013e3181ea2130.
This is a case of a middle-aged woman who experienced subarachnoid haemorrhage secondary to aneurysmal rupture during sexual intercourse.
[3] Krings T, Lasjaunias P, Geibprasert S, Pereira V, & Hans F. (2008). The Aneurysmal Wall. Interventional Neuroradiology, 14(1_suppl), 39-47. https://doi.org/10.1177/15910199080140s107
[4] Paxton S, Knibbs A, & Peckham M. (2020). The Leeds Histology Guide. The Histology Guide - Leeds University. Retrieved 9 November 2020, from https://www.histology.leeds.ac.uk/circulatory/circ_common_str.php.
[5] What You Should Know About Cerebral Aneurysms. American Stroke Association (2020). Retrieved 9 November 2020, from https://www.stroke.org/en/about-stroke/types-of-stroke/hemorrhagic-strokes-bleeds/what-you-should-know-about-cerebral-aneurysms.
[6] Zhou S., Dion P., & Rouleau G. (2018). Genetics of Intracranial Aneurysms. Stroke, 49(3), 780-787. https://doi.org/10.1161/strokeaha.117.018152
[7] Kolhari VB, Bhairappa S, Prasad NM, et al. (2013). Tuberculosis: still an enigma. Presenting as mycotic aneurysm of aorta Case Reports 2013, bcr2013008869.
[8] Physiologically, there's an interesting equation encapsulating the phenomenon: Mean Arterial Pressure (MAP) = Cerebral Perfusion Pressure (CPP) + ICP; MAP refers to the pressure within the artery when pumping blood. Therefore, if the ICP increases gradually, thus equalising MAP, CPP easily drops below the 25 mmHg threshold. Starved of the fruits that blood carry, including ketone bodies (the food for the brain) and oxygen, brain cells fail to function properly.
[9] Reynolds M., Willie J., Zipfel G., & Dacey R. (2011). Sexual intercourse and cerebral aneurysmal rupture: potential mechanisms and precipitants. Journal Of Neurosurgery, 114(4), 969-977. https://doi.org/10.3171/2010.4.jns09975
[10] Williams L, & Brown R. (2013). Management of unruptured intracranial aneurysms. Neurology: Clinical Practice, 3(2), 99-108. https://doi.org/10.1212/cpj.0b013e31828d9f6b