[Note from the authors of “Seriously, Science?”: After nine years with Discover, we’ve been informed that this will be our last month blogging on this platform. Despite being (usually) objective scientists, we have a sentimental streak, and we have spent the last few days reminiscing about the crazy, and often funny, science we have highlighted. Therefore, we have assembled a month-long feast of our favorite science papers. Enjoy!]

Up until now, the scientific literature was pretty much as divided as the internet on whether the large amount of fluid emitted from women upon orgasm represents “real” female ejaculate, or whether it is simply urine (there is a remarkably large body of literature on this topic, both scientific and trashy, and everywhere in between). Previous experiments have focused on determining the liquid’s chemical makeup, finding it to be chemically identical to urine, but these studies ignored the physical source of the copious fluid. Here, the researchers take it one step further by performing ultrasounds before and after ejaculation, as well as testing the biochemical properties of the liquid. It turns out that not only is it chemically identical to urine, but the bladder empties during the period of ejaculation coinciding with orgasm. So there you have it: it’s probably just pee after all!

Nature and Origin of “Squirting” in Female Sexuality.

“INTRODUCTION: During sexual stimulation, some women report the discharge of a noticeable amount of fluid from the urethra, a phenomenon also called “squirting.”

To date, both the nature and the origin of squirting remain controversial. In this investigation, we not only analyzed the biochemical nature of the emitted fluid, but also explored the presence of any pelvic liquid collection that could result from sexual arousal and explain a massive fluid emission.

METHODS: Seven women, without gynecologic abnormalities and who reported recurrent and massive fluid emission during sexual stimulation, underwent provoked sexual arousal. Pelvic ultrasound scans were performed after voluntary urination (US1), and during sexual stimulation just before (US2) and after (US3) squirting. Urea, creatinine, uric acid, and prostatic-specific antigen (PSA) concentrations were assessed in urinary samples before sexual stimulation (BSU) and after squirting (ASU), and squirting sample itself (S).

RESULTS: In all participants, US1 confirmed thorough bladder emptiness. After a variable time of sexual excitation, US2 (just before squirting) showed noticeable bladder filling, and US3 (just after squirting) demonstrated that the bladder had been emptied again. Biochemical analysis of BSU, S, and ASU showed comparable urea, creatinine, and uric acid concentrations in all participants. Yet, whereas PSA was not detected in BSU in six out of seven participants, this antigen was present in S and ASU in five out of seven participants.

CONCLUSIONS: The present data based on ultrasonographic bladder monitoring and biochemical analyses indicate that squirting is essentially the involuntary emission of urine during sexual activity, although a marginal contribution of prostatic secretions to the emitted fluid often exists.”

Related content:
NCBI ROFL: An electrophysiologic study of female ejaculation.
NCBI ROFL: Squirting vs. gushing.
NCBI ROFL: Colombo and the clitoris.