“For there are eunuchs who have been so from birth, and there are eunuchs who have been made eunuchs by others, and there are eunuchs who have made themselves eunuchs for the sake of the kingdom of heaven.” – Matthew 19:10-12.
It is well-known that during puberty there is an increase in the secretion of so-called “sex” hormones (testosterone and estrogens) relative to the period of pre-puberty, and it is commonly believed that the increased secretion results not only in the maturation of the reproductive organs and reproductive function, but also the maturation of the capacity for sexual desire or arousal, genital erection, and orgasm.
The belief is a very old one, and is weakly supported by research on lower mammals (e.g. rodents), which are much more mechanical in their hormone-influenced behavior than human beings. However, the possible effect of “sex” hormones on human behavior is always described using metaphors rather than specific cause-effect relations, and the evidence cited is often anecdotal. Are hormones really so important for human sexual function?
In lower mammals copulation only occurs during ovulation, but careful study of some primates (monkeys) have found that although the number of copulations peaks around ovulation, both males and females initiate copulation throughout the menstrual/hormonal cycle, even during pregnancy, as do humans. I have a clear memory of orgasm-like sensations in my penis at about age six, and first distinct orgasm at about age ten, even though I passed through puberty rather late (14-15). Although ten may be considered the hormonal beginning of adolescence, my first distinct orgasm coincided with learning how to masturbate. It’s possible that if I had learned to masturbate earlier, I would have experienced orgasm earlier. (See: Learning about Love.)
Even some experts voice assent to the supposed contribution of sex hormones to sexual function, but typically without specific reference to any concrete evidence nor any response to some inconvenient counter-evidence, namely some clinical conditions well-known to physiologists: panhypopituitarism (also known as Multiple Pituitary Deficiency), in which untreated individuals never reach puberty but nonetheless may enjoy healthy sexual function; eunuchism: individuals who have no testes or ovaries and nonetheless may enjoy healthy sexual function; and hypogonadism/hypergonadism: undersecretion or oversecretion (respectively) of testosterone and estrogens which is not characterized by an absence of sexual function nor hypersexuality.
In the male normal testosterone levels (relative to body weight) are highest in infancy (age 1-3 months), and even higher than in puberty (age 13-14 years), both absolutely and relative to body weight (1). If testosterone were strictly related to sexual desire and sexual arousal, then infants would be hypersexual – which they obviously aren’t.
Two abnormal testosterone conditions of interest are congenital adrenal hyperplasia (CAH), and androgen insensitivity syndrome (AIS). In untreated CAH hypersexuality is not commonly reported, and in untreated AIS hyposexuality is not a common observation. If testosterone levels were so important in sexual desire or sexual arousal, then hypersexuality or hyposexuality respectively would be observed in these conditions.
We should note that no gland in the human body has a mind of its own, not even the master gland – the pituitary. The increased secretion of testosterone and estrogens during puberty is a consequence of pulsate release of a neurotransmitter, so-called gonadotropic releasing “hormone” (GnRH) by the brain. Saying that sexual function depends on sex hormones merely begs the question, because the secretion of sex hormones is ultimately controlled by the brain. (An exception to this rule is the case of a glandular tumor, in which hypersecretion of the gland’s hormone may occur regardless of brain signals.) It is not even known why secretion of GnRH begins to occur when it does in any individual’s life, nor why such secretions seem to be occurring earlier today than in previous centuries.
Panhypopituitarism (PHP) is a form of dwarfism in which untreated individuals never reach adult stature, as in other forms of dwarfism, but in addition never pass through puberty and never reach what is more appropriately called reproductive maturity (2). In rare cases PHP is the result of physical trauma or a pituitary tumor that is very difficult to treat so the patients often die. More commonly PHP is congenital and if diagnosed early may be treated with replacement hormones. But in those congenital cases where the condition is not diagnosed early or otherwise remains untreated, the affected individuals can and do eventually marry and enjoy healthy sexual function as defined above, although they are infertile.
Eunuchs are men who were physically castrated (usually only the testicles are removed) and have been common throughout history. Although largely deprived of sex hormones and infertile, they can have genital erections and orgasms. In ancient Rome a famous author criticized at least one woman for having sex with a eunuch. One of the last castrated singers in Italy, Giovanni Battista “Giambattista” Velluti, (28 Jan 1780 – 22 Jan 1861), was castrated at age eight and as an adult was well-known for his illicit sexual affairs with married women.
There is also a condition called hypogonadism, in which testosterone and estrogens are undersecreted, with effects primarily on reproductive function (e.g. anovulatory cycles in the female), but not loss of sexual function. Conversely, hypergonadism or oversecretion of testosterone and estrogens has some bad effects, but is not characterized by excessive sexual arousal or any other form of hypersexuality.
Research on non-human primates and lower mammals, which respond to hormonal influence more mechanically, distinguishes between the central effects of estrogens (e.g. female receptivity and proceptivity), and peripheral effects (e.g. attractiveness to males). Estrogen replacement therapy in women who underwent ovarectomy has shown improvement of vaginal dryness and hence comfort to both partners during coitus, but failed to show any increase in female sexual interest.
The administration of anti-androgen drugs to treat prostate cancer entails a risk of reduced “libido,” but such possible side-effects are not universal, which again confirms that sexual function is possible without normal (“mature”) levels of sex hormones. The same is true for chemical castration. There is anecdotal evidence for claims of greatly reduced “libido,” but the effectiveness is not universal: recidivism occasionally occurs among chemically castrated sex offenders. There is a clear possibility that anti-androgen treatment may be confounded by a strong placebo effect. In any case, drugs administered to adults are not necessarily equivalent to natural (unprovoked) low levels of androgens in children.
Hence, there is considerable evidence that increased secretion of so-called sex hormones during puberty or at any other time is not strictly related to healthy sexual function, here defined as the capacity for arousal, genital erection and orgasm. There is good reason to believe that the capacity for healthy sexual function in the absence of so-called “sex” hormones, is not only present in untreated individuals affected by PHP, eunuchism or hypogonadism, but is also present in normal children long before reaching the stage of increased secretion of testosterone or estrogens at puberty. In humans although the capacity for sexual desire or arousal may improve or “peak” after puberty, sexual function is present and robust both before and after adolescence/early adulthood.
Mature sexual behavior is a deliberate attempt and effort to feel sexual pleasure, and even inexperienced children certainly do have a strong desire to feel sexual pleasure, even if the elements of curiosity and play are a larger part of their motivation than in a very experienced adult. Another way of looking at sexual “immaturity” is that many children become mentally castrated through neglect or active shame-training, i.e. they lose their natural capacity for sexual pleasure.
We may say that children are sexually “immature” in the sense that their sexual behavior is different from adults by virtue of the child’s mental castration, but then the distinction has lost much of its significance. The popular belief that children are naturally or inevitably asexual before puberty (i.e. reproductive maturity) is clearly mistaken and contradicts what is known about human physiology.
That mistaken belief must be explained by other factors, such as historical ignorance of human physiology, or the convenience of such a belief to support certain financial interests, political expediency, or ancient religious ideologies. The belief that sexual function suddenly appears at puberty, so sex play in childhood is unnecessary and useless, supports the traditional mental castration of girls.
Traditionally, mental maturity has been conceived as a certain “plateau” that is reached at some age, characterized by the ability to reason effectively and autonomously. However, in reality some individuals reach a low plateau of reasoning very early in life, never learning the principles of elementary logic and unable to reason autonomously without depending on some simple authority (substitute caregiver) as a crutch, while other individuals continue changing and developing their mental effectiveness and autonomy throughout their lives.
Choosing to call any level of mental development “maturity” is necessarily arbitrary. In Western countries some research has focused on understanding such concepts as freedom of speech as a measure of mental maturity, even though many “mature” individuals never develop an awareness that the abstract right to freedom of speech has little practical value in daily life if what you want to say is widely considered politically incorrect.
On a more practical note, many adults arbitrarily considered mentally “mature” (by virtue of having counted their birthdays) are unable to stop smoking even when informed that smoking during pregnancy entails serious health risks for their child. The same is true for breastfeeding. Many mothers considered mentally “mature” decline to breastfeed their babies despite the well-known benefits of breastfeeding, and despite the well-known dangers of infant bottle formula.
More specific research on sexual decision making is needed to determine if there is any inherent biological defect in mental capacity before puberty (as opposed to culturally imposed mental castration) that renders pre-pubertal individuals incompetent to understand alternatives and consequences of sexual choices, i.e. choosing to enjoy sex play or not. (See Age of Consent).
1. Forest, M.G. (Ed.). Androgens in Childhood. (Karger, 1989).
2. Guyton, Arthur C. and Hall, John E. Textbook of Medical Physiology, 11th ed. Saunders, 2005.