Reproduction involves the biology whereby a man impregnates a woman. A man’s arousal cycle is an essential (and so automatic) part of this process. Responsiveness including erection, ejaculation of sperm and the associated orgasm are all key aspects of male sexuality. When boys first start ejaculating, they have the highest responsiveness of any time in their lives. From adolescence onwards male responsiveness declines very slowly and gradually. Many of the men with the highest responsiveness start ejaculating earlier than the average boy (before age 13). Many of these (particularly the more educated) use masturbation as a sexual outlet.
Alfred Kinsey charted weekly orgasm frequencies for men and women. At age 20 they were 2.25 for men and 0.4 for women. At age 30 1.8 for men and 0.5 for women. At age 40 1.4 for men and 0.5 for women. At age 50 1.1 for men and 0.45 for women. At age 60 0.7 for men and 0.4 for women. So women’s responsiveness changes little over their lifetimes but men’s falls very gradually from adolescence to old age. At any age, men’s responsiveness is always greater than women’s on average.
Reproductively speaking a woman is a sitting duck. She doesn’t need to do anything except put herself in a position where a man ejaculates into her vagina (or close to it). Sperm can sometimes make their way into the vagina if a man ejaculates just outside. Even anal sex may result in pregnancy. A woman is potentially capable of being impregnated any time she has intercourse. Ovulation occurs at a specific point during her monthly cycle.
A woman’s cycle can vary considerably but may involve a period of 5 days followed by 28 days of not having a period. There is a great deal of variation not only from woman to woman but also for one woman from month to month. A woman can conceive (if sperm are present) during the few days after she has ovulated. To know the days when she is fertile, she would need to keep a temperature chart. Few women ever do this and simply assume that they may conceive any time after their period ends.
The active ingredient is a man’s motivation to engage in intercourse. A woman needs only to make herself attractive and be sexually willing. Various factors affect a woman falling pregnant but regular intercourse over a period of a few months is likely to result in pregnancy. A woman only needs regular intercourse for as long as she needs to conceive. Male responsiveness (as for other primates) has evolved so that men want intercourse much more regularly than this. A woman offers intercourse frequently enough to motivate a man to support her. This female behaviour together with male responsiveness are crucial to human reproduction.
The function of male orgasm is to trigger the ejaculation of sperm. When a man has an orgasm, he always ejaculates. The biological act of ejaculation is rewarded with orgasm. A man can enjoy both as separate phenomena. Ejaculation is physical and orgasm is psychological. If we are to feel psychologically satisfied, then we want to have a ‘good orgasm’. Our motivation to engage in sexual activity is evidenced by how often we think or dream about sex. Men have sex dreams that culminate in orgasm.
Frequency of masturbation is an indication of responsiveness. This is why male masturbation is much more common and why men masturbate much more frequently than women do. Masturbation frequencies are highest among men who become adolescent first. Around 99% of such men masturbate compared with 93% of men who reach adolescence later than the average (13 years old). Some young men masturbate many times a day.
Not every man masturbates but on average more men masturbate more frequently than women do. Men masturbate to orgasm in a minute or less. Typical male speeds to orgasm are quicker with masturbation (than intercourse) but may be less satisfying (for some men). Many women (30% of Kinsey’s sample or about 1,800 women) openly acknowledge that they are never or rarely aroused. Women are much less responsive than men are. This is about balancing effort and reward. First a woman has to make much more conscious effort to engage on achieving arousal and second the rewards of orgasm are nowhere near as critical to women as they are to men. Kinsey found that women orgasm on average once every two weeks regardless of age.
No one discovers orgasm because someone else tells them what they should stimulate. We discover orgasm because of the way our mind responds to erotic stimuli. Once we are aroused, our bodies indicate to us the anatomy that is physically aroused (tumescence or erection). Both the G-spot and the clitoris have tried to explain how women might orgasm with a lover. But science does not define our responses. It is the other way around. Our responses define our understanding of responsiveness.
By 15 years of age, 92 per cent of the males have had orgasm, but at that same age less than a quarter of the female have had such experience; and the female population is 29 years old before it includes as high a percentage of experienced individuals as is to be found in the male curve at 15. (Alfred Kinsey 1948)