Below are abstracts with my comments. I've studied and searched, and found all the abstracts (I think) on testosterone (T) levels and orgasm/ejaculation.
A lot of questions arise concerning T levels and ejaculation, and non-ejaculation, and the "hangover", or abstinence, or excessive porn use.
The results of studies are all over the map on T levels and ejaculation. My opinion is that T levels has little to do with any of the above. Look elsewhere - as in the brain - for answers to your questions.
Note the very last study - how men with severe impotence (years for many) have same levels of T as "normal" sexually active men.
Also, note this first study - yes T spikes at day 7, but thats not significant to behavior, or mood. It is a marker of a cycle, but in of itself it is not THE cycle.
A RESEARCH ON THE RELATIONSHIP BETWEEN EJACULATION AND SERUM TESTOSTERONE LEVEL IN MEN.
Jiang M, Xin J, Zou Q, Shen JW. J Zhejiang Univ Sci. 2003 Mar-Apr;4(2):236-40.
The purpose of this study is to gain understanding of the relationship between ejaculation and serum testosterone level in men. The serum testosterone concentrations of 28 volunteers were investigated daily during abstinence periods after ejaculation for two phases.
The authors found that the fluctuations of testosterone levels from the 2nd to 5th day of abstinence were minimal. On the 7th day of abstinence, however, a clear peak of serum testosterone appeared, reaching 145.7% of the baseline ( P < 0.01). No regular fluctuation was observed following continuous abstinence after the peak.
Ejaculation is the precondition and beginning of the special periodic serum testosterone level variations, which would not occur without ejaculation. The results showed that ejaculation-caused variations were characterized by a peak on the 7th day of abstinence; and that the effective time of an ejaculation is 7 days minimum. These data are the first to document the phenomenon of the periodic change in serum testosterone level; the correlation between ejaculation and periodic change in the serum testosterone level, and the pattern and characteristics of the periodic change.
COMMENT: This one day peak indicates a cycle initiated by orgasm. It does not slowly rise to this level, or slowly decline, it’s a spike. At all other times the levels of testosterone are in normal ranges. Really get that this is a single spike. This single spike occurs due to signals from the brain. Spikes of hormones are often used to kick in other hormones or events. Sometimes a spike in hormone parallels events elsewhere in the body. This spike is not the hangover, but is a marker for an event
ORGASMIC FREQUENCY AND PLASMA TESTOSTERONE LEVELS IN NORMAL HUMAN MALES
JournalArchives of Sexual Behavior April 23, 2005
Twenty males participated in a 2-month study examining the relationship between 8 a.m. plasma testosterone levels and orgasmic frequency. Within subjects, higher levels of testosterone are associated with periods of sexual activity. Over subjects, however, the direction of the relationship is reversed. Mean testosterone levels were higher for sexually less active individuals.
COMMENT: Average testosterone levels where higher in less sexually active men. But –sexual activity increased testosterone levels in individuals – on average.
ENDOCRINE RESPONSE TO MASTURBATION-INDUCED ORGASM IN HEALTHY MEN FOLLOWING A 3-WEEK SEXUAL ABSTINENCE.
Exton MS, Krüger TH, Bursch N, Haake P, Knapp W, Schedlowski M, Hartmann U.
World J Urol. 2001 Nov;19(5):377-82.
This current study examined the effect of a 3-week period of sexual abstinence on the neuroendocrine response to masturbation-induced orgasm. Hormonal and cardiovascular parameters were examined in ten healthy adult men during sexual arousal and masturbation-induced orgasm. Blood was drawn continuously and cardiovascular parameters were constantly monitored. This procedure was conducted for each participant twice, both before and after a 3-week period of sexual abstinence. Plasma was subsequently analysed for concentrations of adrenaline, noradrenaline, cortisol, prolactin, luteinizing hormone and testosterone concentrations. Orgasm increased blood pressure, heart rate, plasma catecholamines and prolactin. These effects were observed both before and after sexual abstinence. In contrast, although plasma testosterone was unaltered by orgasm, higher testosterone concentrations were observed following the period of abstinence. These data demonstrate that acute abstinence does not change the neuroendocrine response to orgasm but does produce elevated levels of testosterone in males.
COMMENT: Elevated testosterone levels following abstinence. BUT, orgasm did not alter testosterone in the short-term
NEUROENDOCRINE AND CARDIOVASCULAR RESPONSE TO SEXUAL AROUSAL AND ORGASM IN MEN.
Psychoneuroendocrinology. 1998 May;23(4):401-11.
Data regarding the neuroendocrine response pattern to sexual arousal and orgasm in man are inconsistent. In this study, ten healthy male volunteers were continuously monitored for their cardiovascular and neuroendocrine response to sexual arousal and orgasm. Blood was continuously drawn before, during and after masturbation-induced orgasm and analyzed for plasma concentrations of adrenaline, noradrenaline, cortisol, luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, growth hormone (GH), beta-endorphin and testosterone. Orgasm induced transient increases in heart rate, blood pressure and noradrenaline plasma levels. Prolactin plasma levels increased during orgasm and remained elevated 30 min after orgasm. In contrast, none of the other endocrine variables were significantly affected by sexual arousal and orgasm.
COMMENT: short-term testosterone levels not affected by orgasm. Which opposes the following study
ENDOCRINE EFFECTS OF MASTURBATION IN MEN
K Purvis, BM Landgren, Z Cekan, and E Diczfalusy
Journal of Endocrinology, Vol 70, Issue 3, 439-444 1976 by Society for Endocrinology
The levels of pregnenolone, dehydroepiandrosterone (DHA), androstenedione, testosterone, dihydrotestosterone (DHT), oestrone, oestradiol, cortisol and luteinizing hormone (LH) were measured in the peripheral plasma of a group of young, apparently healthy males before and after masturbation. The same steroids were also determined in a control study, in which the psychological anticipation of masturbation was encouraged, but the physical act was not carried out. The plasma levels of all steroids were significantly increased after masturbation, whereas steroid levels remained unchanged in the control study. The most marked changes after masturbation were observed in pregnenolone and DHA levels. No alterations were observed in the plasma levels of LH. Both before and after masturbation plasma levels of testosterone were significantly correlated to those of DHT and oestradiol, but not to those of the other steroids studied. On the other hand, cortisol levels were significantly correlated to those of pregnenolone, DHA, androstenedione and oestrone. In the same subjects, the levels of pregnenolone, DHA, androstenedione, testosterone and DHT, androstenedione and oestrone. In the same subjects, the levels of pregnenolone, DHA, androstenedione, testosterone and DHT in seminal plasma were also estimated; they were all significantly correlated to the levels of the corresponding steroid in the systemic blood withdrawn both before and after masturbation. As a practical consequence, the results indicate that whenever both blood and semen are analysed, blood sampling must precede semen collection.
COMMENT: short-term testosterone levels were elevated by orgasm, which is countered by several other studies
A CYCLE OF PLASMA TESTOSTERONE IN THE HUMAN MALE.
J Clin Endocrinol Metab. 1975 Mar;40(3):492-500.
The object of the study was to assess the lability of testosterone levels in plasma of normal human males over a long period of time and to search for periodicities in changing levels. Blood samples obtained from 20 healthy young men every second day for 2 months were assayed for total testosterone concentration by radioligand saturation analysis with late-pregnancy plasma. The flucturations of plasma testosterone levels over the total time span were substantial for most individuals; the coefficients of variation ranged from 14 to 42% (median 21%). The presence of periodic functions in these fluctuations was tested by 4 different, relatively independent methods. Close agreement among at least 3 analytic methods was found for 12 out of the 20 subjects. These 12 subjects had cycles of plasma testosterone levels with periods ranging between 8-30 days, with a cluster of periods around 20-22 days. The majority of such cycles were significant at least at the 5% level. The mean amplitudes of these cycles ranged from 9 to 28% of the subjects' mean testosterone levels (average 17%).
COMMENTS: Men have natural fluctuations of testosterone – averaging 17%. Not only that but many other things affects T levels, including exercise, mood, social rank, drugs, alcohol, etc.
PLASMA TESTOSTERONE LEVELS OF SEXUALLY FUNCTIONAL AND DYSFUNCTIONAL MEN.
Schwartz MF, Kolodny RC, Masters WH.
Arch Sex Behav. 1980 Oct;9(5):355-66.
Plasma testosterone levels in a group of 341 men with sexual dysfunction were compared to those in 199 men with normal sexual function. All subjects were participants in a 2-week intensive conjoint sex therapy program at the Masters & Johnson Institute. Testosterone determinations were made using radioimmunoassay methods after column chromatography; all blood samples were obtained on the second day of therapy between 8:00 and 9:00 a.m. after an overnight fast. Circulating levels of testosterone in men with normal sexual function (mean 635 ng/dl) were not significantly different from testosterone values in sexually dysfunctional men (mean 629 ng/dl). However, men with primary impotence (N = 13) had significantly higher testosterone levels than men with secondary impotence (N = 180), with mean levels of 710 and 574 ng/dl, respectively (p < 0.001). The mean testosterone level for men with ejaculatory imcompetence was 660 ng/dl (N = 15), while for men with premature ejaculation the mean was 622 ng/dl (N = 91). Plasma testosterone concentrations were not related to therapy outcome but were correlated negatively with age of patients.
COMMENTS: As it says – not much difference in T levels between impotent and normal guys. Conclusion should be that many of the impotent men are not having orgasms. Further conclusion is that testosterone levels are not significant players in post-ejaculatory experience – including a hangover – since long term differences ejaculators and non-ejaculators does not occur.