Lack of alteration of serum gonadotropins in men and women following sexual intercourse

Sexual incentive motivation, sexual behavior, and general arousal: Do rats and humans tell the same story?

Sexual incentive stimuli activate sexual motivation and heighten the level of general arousal. The sexual motive may induce the individual to approach the incentive, and eventually to initiate sexual acts. Both approach and the ensuing copulatory interaction further enhance general arousal. We present data from rodents and humans in support of these assertions. We then suggest that orgasm is experienced when the combined level of excitation surpasses a threshold. In order to analyze the neurobiological bases of sexual motivation, we employ the concept of a central motive state. We then discuss the mechanisms involved in the long- and short-term control of that state as well as those mediating the momentaneous actions of sexual incentive stimuli. This leads to an analysis of the neurobiology behind the interindividual differences in responsivity of the sexual central motive state. Knowledge is still fragmentary, and many contradictory observations have been made. Nevertheless, we conclude that the basic mechanisms of sexual motivation and the role of general arousal are similar in rodents and humans.

Functional significance of men's testosterone reactivity to social stimuli

Rapid testosterone fluctuations in response to social stimuli are observed across a wide range of species, and the highly conserved nature of these fluctuations suggests an adaptive function. This paper reviews the current literature on testosterone reactivity, primarily in human males, and illustrates how life-history theory provides an adequate theoretical framework to interpret findings. The review is structured around supporting evidence suggesting that situations implicated in mating effort either directly (e.g., interactions with a mate) or indirectly (e.g., intrasexual competition) are generally associated with a brief elevation of testosterone, while situations implicated in parenting effort (e.g., nurturant interactions with offspring) are generally associated with a decline in testosterone. Further, we discuss how these fluctuations in testosterone have been linked to future behaviors, and how situational, motivational, and physiological variables moderate the interplay between social stimuli, testosterone reactivity, and behavior. Supporting the notion that testosterone can play a causal role in modulating behavior in response to social stimuli, we also summarize recent single administration studies examining the effects of testosterone on physiology, neurobiology, and behavior. A conceptual model provides links between supported findings, and hypothesized pathways requiring future testing.

Influence of ovarian manipulation on reproductive endocrinology in polycystic ovarian syndrome and regularly cycling women

OBJECTIVE

Little is known about the function of the ovarian neuronal network in humans. In many species, copulation influences endocrinology through this network. As a first step, the possible influence of ovarian mechanical manipulation on pituitary and ovarian hormones was evaluated in polycystic ovarian syndrome (PCOS) and regularly cycling women.

DESIGN

Prospective case-control study (2008-2010).

METHODS

Ten PCOS women (Rotterdam criteria) undergoing ovulation induction with recombinant-FSH and ten normal ovulatory controls were included in an academic fertility clinic. In the late follicular phase blood was drawn every 10 min for 6 h. After 3 h the ovaries were mechanically manipulated by moving a transvaginal ultrasound probe firmly over each ovary ten times. Main outcome measures were LH and FSH pulsatility and ovarian hormones before and after ovarian manipulation.

RESULTS

All PCOS patients showed an LH decline after the ovarian manipulation (before 13.0 U/l and after 10.4 U/l, P<0.01), probably based on a combination of a longer LH pulse interval and smaller amplitude (P=0.07). The controls showed no LH change (before 9.6 U/l and after 9.3 U/l, P=0.67). None of the ovarian hormones (estradiol, progesterone, anti-Müllerian hormone, inhibin B, androstenedione and testosterone) changed in either group.

CONCLUSIONS

Ovarian mechanical manipulation lowers LH secretion immediately and typically only in preovulatory PCOS patients. The immediate LH change after the ovarian manipulation without any accompanying ovarian hormonal changes point to nonhormonal communication from the ovaries to the pituitary. A neuronal pathway from the ovaries communicating to the hypothalamic-pituitary system is the most reasonable explanation.

Sexual fantasies and gender/sex: a multimethod approach with quantitative content analysis and hormonal responses

Research links explicit sexuality (e.g., physical attraction and pleasure) to high testosterone (T) and nurturance (loving contact) to low T. Engaging in sexual fantasy, which can include explicit sexual and nurturant elements, increases T in women but not in men. We examined whether individual differences in the explicit sexual and nurturant content of fantasy were linked with T or with estradiol (E2). In addition, we explored whether fantasy content differed or overlapped by gender/sex. Participants (26 women, 23 men) provided saliva samples for hormones before and after imagining a self-defined positive sexual encounter and responding to open-ended questions about the situation they imagined. We systematically content-coded responses for explicit sexual and nurturant content. In men, lower inclusion of nurturant content predicted larger T responses to fantasy. Fantasy content was not linked with T in women or with E2 in women or men. Women and men did not differ significantly in explicit sexual and nurturant content. Our findings suggest that individual experiences of fantasy as more or less nurturant affect T in men, provide support for the Steroid/Peptide Theory of Social Bonds, and highlight the value of integrating hormones and content analysis to investigate research questions relevant to sexuality and gender/sex.

Sexual thoughts: links to testosterone and cortisol in men

Sexual stimuli increase testosterone (T) or cortisol (C) in males of a variety of species, including humans, and just thinking about sex increases T in women. We investigated whether sexual thoughts change T or C in men and whether hormone measures (baseline, post-activity, and changes) correlate with psychological sexual arousal. We used the Imagined Social Situation Exercise to assess how hormones respond to and correlate with sexual thoughts and arousal relative to three control conditions: neutral, stressful, and positive. A total of 99 men provided a baseline saliva sample, imagined and wrote about a sexual or control situation, and provided a second saliva sample 15 min later. Results indicated that, for participants in the sexual condition, higher baseline and post-activity C corresponded to larger increases in self- reported sexual and autonomic arousal. Although sexual thoughts increased sexual arousal, they did not change T or C compared to control conditions. Our results suggest that sexual thoughts are not sufficient to change T or C in men, but C may facilitate sexual arousal by directing energy towards a sexual situation.

Acute stress may induce ovulation in women

BACKGROUND

This study aims to gather information either supporting or rejecting the hypothesis that acute stress may induce ovulation in women. The formulation of this hypothesis is based on 2 facts: 1) estrogen-primed postmenopausal or ovariectomized women display an adrenal-progesterone-induced ovulatory-like luteinizing hormone (LH) surge in response to exogenous adrenocorticotropic hormone (ACTH) administration; and 2) women display multiple follicular waves during an interovulatory interval, and likely during pregnancy and lactation. Thus, acute stress may induce ovulation in women displaying appropriate serum levels of estradiol and one or more follicles large enough to respond to a non-midcycle LH surge.

METHODS

A literature search using the PubMed database was performed to identify articles up to January 2010 focusing mainly on women as well as on rats and rhesus monkeys as animal models of interaction between the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes.

RESULTS

Whereas the HPA axis exhibits positive responses in practically all phases of the ovarian cycle, acute-stress-induced release of LH is found under relatively high plasma levels of estradiol. However, there are studies suggesting that several types of acute stress may exert different effects on pituitary LH release and the steroid environment may modulate in a different way (inhibiting or stimulating) the pattern of response of the HPG axis elicited by acute stressors.

CONCLUSION

Women may be induced to ovulate at any point of the menstrual cycle or even during periods of amenorrhea associated with pregnancy and lactation if exposed to an appropriate acute stressor under a right estradiol environment.

The effects of partner togetherness on salivary testosterone in women in long distance relationships

The present study examined whether women's testosterone levels are influenced by being with a sexual and romantic partner after a period of sexual abstinence. Women in long distance relationships (n=15) provided five saliva samples: at least 1 week before seeing their partner (and at least 2 weeks since their last visit), the day before seeing their partner, when they were with their partner but prior to engaging in sexual activity, the day after their first sexual activity, and 3 days after they were separated from their partners. Salivary testosterone was lowest when participants had been away from their partners for at least 2 weeks and highest the day before they were to see their partners and the day after sexual activity. Results from this study indicated that women's testosterone increased both the day before they were with their partners and they day after they first engaged in sexual activity. However, something about initially reuniting with their partners returned their testosterone to baseline levels, which may be an effect of being in the same location as a partner, or just a state fluctuation due to nervousness or other psychological state.

Are gonadal steroids linked with orgasm perceptions and sexual assertiveness in women and men?

Past findings suggest links between orgasms and testosterone (T), as well as sexuality and estradiol (E), and we examined hormone-orgasm links in this study via two hypotheses (below). Participants were 86 women and 91 men who provided a saliva sample and completed a demographics questionnaire, the Orgasm Checklist (Mah and Binik, 2002), the Hurlbert (1991) Index of Sexual Assertiveness, and the Sexual Desire Inventory (Spector and Fremeth, 1996). Results supported the first hypothesis of correlations between T and positive orgasm experience in women, specifically with the relaxation, soothing, and peaceful items in both partnered and solitary orgasm contexts. Results also indicated correlations between E and flooding and spreading items in a solitary orgasm context. There were no associations between hormones and men's perceptions of their orgasm experiences. There was no support for the second hypothesis of associations between higher T and more sexual assertiveness. Post hoc analyses showed associations between E and women's sexual desire, and T and men's sexual desire. We discuss implications of these findings including that solitary vs. partnered orgasm experiences may differ, and suggest that T might be associated with perceptions of psychological experiences of orgasms, and E might be associated with perceptions of physical experiences of orgasms.

Associations between testosterone secretion and sexual activity in women

Some studies show an increase in testosterone (T) after sexual activity; this literature has inconsistent findings, focuses mostly on men, and does not employ control activities. The present study examined within-subject effects of intercourse versus control activities (cuddling; exercise) on salivary T. The initial sample included 49 women (mostly heterosexual), though not all participants returned all samples or engaged in all activities, leaving a smaller sample for endocrine analyses (n=16). Participants attended an initial session in the laboratory where they completed questionnaires, and then engaged in the activities on their own. On three separate nights, they provided pre-activity, post-activity, and next-morning saliva samples and completed brief questionnaires at the last two timepoints. Women's T was higher pre-intercourse than pre-control activity. Women's T was also higher post-intercourse than post-control activity, though the percent change in T from pre- to post-activity was highest for cuddling, then intercourse, then exercise. Next-morning T did not differ by activity. Data pointed to an association between T and orgasming, sexual desire, and relationship commitment. Analyses on post-activity appraisals suggest that the close intimate physicality of a sexual and non-sexual nature can affect T and be beneficial in short-term and perhaps longer-lasting ways for women's sexuality and relationships.

Neuroendocrine response to film-induced sexual arousal in men and women

The psychoneuroendocrine responses to sexual arousal have not been clearly established in humans. However, we have demonstrated previously that masturbation-induced orgasm stimulates cardiovascular activity and induces increases in catecholamines and prolactin in blood of both males and females. We presently investigated the role of orgasm in producing these effects. Therefore, in this study parallel analysis of prolactin, adrenaline, noradrenaline, and cortisol concentrations, together with cardiovascular variables of systolic/diastolic blood pressure and heart rate were undertaken during film-induced sexual arousal in nine healthy adult men and nine healthy adult women. Blood was drawn continuously via an indwelling cannula and connected tubing system passed through a mini-pump. In parallel, the cardiovascular parameters were recorded continuously via a computerised finger-cuff sensor. Subjective sexual arousal increased significantly in both men and women during the erotic film, with sexual arousal eliciting an increase in blood pressure in both males and females, and plasma noradrenaline in females only. In contrast, adrenaline, cortisol and prolactin levels were unaffected by sexual arousal. These data further consolidate the role of sympathetic activation in sexual arousal processes. Furthermore, they demonstrate that increases in plasma prolactin during sexual stimulation are orgasm-dependent, suggesting that prolactin may regulate a negative-feedback sexual-satiation mechanism.

Cardiovascular and endocrine alterations after masturbation-induced orgasm in women

OBJECTIVE

The present study investigated the cardiovascular, genital, and endocrine changes in women after masturbation-induced orgasm because the neuroendocrine response to sexual arousal in humans is equivocal.

METHODS

Healthy women (N = 10) completed an experimental session, in which a documentary film was observed for 20 minutes, followed by a pornographic film for 20 minutes, and another documentary for an additional 20 minutes. Subjects also participated in a control session, in which participants watched a documentary film for 60 minutes. After subjects had watched the pornographic film for 10 minutes in the experimental session, they were asked to masturbate until orgasm. Cardiovascular (heart rate and blood pressure) and genital (vaginal pulse amplitude) parameters were monitored continuously throughout testing. Furthermore, blood was drawn continuously for analysis of plasma concentrations of adrenaline, noradrenaline, cortisol, prolactin, luteinizing hormone (LH), beta-endorphin, follicle-stimulating hormone (FSH), testosterone, progesterone, and estradiol.

RESULTS

Orgasm induced elevations in cardiovascular parameters and levels of plasma adrenaline and noradrenaline. Plasma prolactin substantially increased after orgasm, remained elevated over the remainder of the session, and was still raised 60 minutes after sexual arousal. In addition, sexual arousal also produced small increases in plasma LH and testosterone concentrations. In contrast, plasma concentrations of cortisol, FSH, beta-endorphin, progesterone, and estradiol were unaffected by orgasm.

CONCLUSIONS

Sexual arousal and orgasm produce a distinct pattern of neuroendocrine alterations in women, primarily inducing a long-lasting elevation in plasma prolactin concentrations. These results concur with those observed in men, suggesting that prolactin is an endocrine marker of sexual arousal and orgasm.

Neuroendocrine and cardiovascular response to sexual arousal and orgasm in men

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.

Male and female salivary testosterone concentrations before and after sexual activity

Salivary testosterone concentrations were measured in male and female members of four heterosexual couples on a total of 11 evenings before and after sexual intercourse and 11 evenings on which there was no intercourse. Testosterone increased across the evening when there was intercourse and decreased when there was none. The pattern was the same for males and females. Early evening measured did not differ on the two kinds of days, suggesting that sexual activity affects testosterone more than initial testosterone affects sexual activity.

Hypothalamic involvement in sexuality and hostility: comparative psychological aspects

Evidence presented in this article shows the representation of sexual and aggressive behaviors at the level of the hypothalamus to be more prominent than in all other brain areas involved. Indeed, there are good arguments to attribute a central position to the hypothalamus within larger structural systems encompassing the limbic system, where aspects of the behaviors involved can be influenced. So far, however, the arguments are purely descriptive and factual and do not contribute much to answering questions about hypothalamic function: the grounds for and consequences of this massive representation of apparently almost all emotionally relevant social behavioral complexes, so universally established in a diversity of species, still has to be detected. A second and equally important aspect of hypothalamic function obviously has to be related to its central position within various hormonal systems. The present article concentrated on the acute dynamics and behavioral significance of activation of the pituitary-adrenocortical and pituitary-gonadal axes. Evidence indicates that the unconditioned behavioral stimuli or the consequences of behavior, but also stimuli conditioned to emotionally relevant events, may drastically alter hypothalamic hormonal regulation. Most importantly, these hormonal consequences in themselves again seem to determine further behavior and responses in relevant situations. The evidence presented with respect to reward and aversion, associated with alterations of specific hormones of the gonadal axis, may add a new dimension to our understanding of psychoendocrine functions of the hypothalamus (see also Gary, 1975; Leshner et al., 1981; Carey, 1987). Psychologically, such data can be taken as an argument for a more thorough study of the relation between memory processes and emotion (Bower et al., 1981). However fragmentary and incomplete this review may be, it will be clear that hypothalamic substrates and directly related areas, as well as affiliated hormonal mechanisms, play a central role in many of the most complex motivational and emotional syndromes and disorders. The prime idea in this is that the psychological concomitants of hypothalamic (dys)function are as much output as input, and as much the consequences as the cause within related syndromes. Such a view places the hypothalamus at the core of psychological theories of emotion and motivation, which from their most early origin have been heavily set towards hormonal and humoral changes and their relationships with psychological experience.(ABSTRACT TRUNCATED AT 400 WORDS)

Coitus-induced ovulation and its implications for estimates of some reproductive parameters

It is estimated here that, at the time of conception, the mean coital rate of young women who subsequently bear DZ twins is about 6% higher than that of the general population of young married women. This differential seems too small to account wholly for the greater promptness in conceiving DZ twins. Accordingly, it is suggested that coital rate is associated with DZ twinning in two ways. The major link seems to be indirect and mediated by erotic response which causes an increase in gonadotrophin levels and thus in double ovulation. In a minority of cases, frequent coitus may give rise to DZ twins via superfecundation, but it seems that, in human beings, the corpus luteum of one ovum will usually inhibit fertilization of any further ova after a short interval. The evidence presented here, though indirect, seems to suggest that, under particularly erotic conditions, double ovulation is sometimes induced. It seems reasonable to infer that coitus also occasionally provokes or accelerates single ovulations, thus impugning some rhythm methods of contraception. But there seems no very good evidence that rape induces ovulation. Some notes are added on the implications of induced ovulation for estimates of fecundability and of the length of the fertile period.

The endocrine effects of visual erotic stimuli in normal men

Endocrine responses to erotic stimulation in the laboratory were assessed in eight normal subjects. Each subject was tested on two occasions. On one occasion only neutral stimuli were involved. After 15 min baseline, 30 min of films were shown. For the erotic condition on the other occasion, two 10-min erotic films were interspersed with 10 min of neutral film. Fifteen-minute blood samples were taken from the start of each test and continued for 5 hr after the films. Plasma was assayed for testosterone, LH, prolactin, cortisol, ACTH and beta-endorphin. Urine was collected for 4 hr before and 4 hr after the films; this was assayed for adrenaline, noradrenaline and dopamine. Sexual arousal occurred in response to the erotic films in all subjects, as shown by erectile and subjective responses. There were no significant changes in hormone or catecholamine levels following either the erotic or the neutral stimuli, except for a rise in cortisol during the neutral but not the erotic film. These results indicate that in the laboratory, substantial sexual response can occur without accompanying endocrine or biochemical changes.

Endocrine, psychological and genital response to sexual arousal in men

The endocrine, genital, and cognitive--affective responses of sexually functional men were compared under sexually arousing and non-arousing conditions. Sexually aroused subjects showed significantly higher serum luteinizing hormone concentrations than non-aroused subjects. Testosterone concentration was correlated with higher levels of penile response, but it did not prime further sexual arousal. Cortisol and prolactin concentrations decreased in both groups, more in the non-aroused group, and appeared to both inhibit and facilitate sexual response, depending on the level of anxiety reported by the subjects. Cortisol was correlated with self-reported worry, and testosterone with relaxation. These results support a multidimensional approach to the endocrine study of sexual arousal that includes both cognitive and genital response components.

Immunoreactive insulin in serum and seminal plasma of diabetic and nondiabetic men and its role in the regulation of spermatozoal activity

Concentrations of immunoreactive insulin (IRI) and, in some cases, testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured in serum and seminal plasma (SP). IRI levels were usually higher in SP. They were unaffected by masturbation; circulating testosterone, LH, and FSH levels were also unaffected. The IRI concentration was higher in the second (vesicular) fraction of split ejaculates. Semen quality was unrelated to IRI in SP in normal and diabetic (chlorpropamide-maintained) men. The addition of insulin in vitro to washed spermatozoa from diabetic and nondiabetic men had no effect on oxygen and glucose uptake or on lactate production and spermatozoal motility. Furthermore, administration of L-arginine to infertile men for 3 months (4 gm/day) was followed in four of seven men by significant increases in IRI concentrations in blood and SP. However, neither semen quality nor fertility was improved.

A study of the relationship between coitus and the luteinizing hormone surge

Twenty-seven wives participating in a study of sexual activity patterns had identifiable shifts in basal body temperature and midcycle surges of serum luteinizing hormone (LH). When sexual activity data were examined using the LH surge as a centering point, it was observed that the day before the LH surge had only an average probability of coitus and organism. These findings suggest that neither coitus nor orgasm often triggers ovulation in humans. This cannot be taken as evidence that coitus-induced ovulation never occurs.