About 90% of men and 65% of women have orgasms from sexual intercourse with their consenting partners. Not surprising, these percentages vary based on a variety of factors, including the type of intercourse people are engaging in. For example, it is common knowledge (at least it should be!), the probability of a person having an orgasm increases and decreases relative to the underside of the glans penis and the glans clitoris being stimulated during intercourse. What is surprising and not-so-common knowledge is 100% of men and 94% of women receiving anal intercourse with their consenting partners report having orgasms.


When outside the body and within blood, semen, vaginal fluid, rectal fluid, or breast milk, the human immunodeficiency virus (HIV), the virus that causes acquired immune deficiency syndrome (AIDS) has a relatively short and fragile existence, and can be easily eliminated with soap, bleach, peroxide, or some spermicides.

There is a significant caveat when it comes to spermicides eliminating in vitro HIV. Spermicides containing nonoxynol-9 (N9) do not eliminate HIV infection because N9 irritates, and even causes inflammation of the soft tissues in the mouth, and linings of the vagina and rectum. N9 may even increase the risk of HIV…

True or False: Petroleum jelly, Vaseline Intensive Care, baby oil, and Nivea are good lubricants to use with a condom or diaphragm.

This statement is FALSE because all the lubricants listed contain petroleum. Petroleum-based personal lubricants break-down condoms and diaphragms on a microscopic-level, making them porous, and allowing sperm, bacteria, or viruses to pass through them — negating their birth-control or safe-sex effectiveness.

Thus, I only recommend petroleum-based personal lubricants used with condoms or diaphragms for people who want to gain a child or an STI (sexually transmitted infection).

With this said, and knowing the anus has no natural capacity…

Human sexuality scientists say seemingly controversial things.

For example, one of the things they say is “about a quarter of US men have sexual experiences with another man at least once during their lifetimes.” Human sexuality scientists say this even though only about 8% of US men report having sex with another man and only about 5% of US men identify as being gay.

So, what gives with these percentages being different from one another? They should be equal. Or should they?

The percentage of men identifying as being gay widely varies from one culture to the next with culture…

Answer me this: By only looking at a person — and knowing nothing else about them, can you reliably determine if they are gay or not?

Image from source

You are probably thinking you can do this, and you are probably wrong in your thinking.

Do not worry, you are not alone in your probabilistically wrong thinking, as a bunch of scientific research studies think this is possible too. But these studies back-up their thinking with accuracy rates ranging between only 55% and 65%. And remember, random guessing about something that either is or is not, yields 50% accuracy rates.

Most studies measuring people’s ability to determine whether a person is gay or not by only looking at them (gaydar), fail to control for subject biases and do not…

Pregnancy is caused by conception, the coming together of one sperm and one ovum, whereas contraception is keeping sperm and ova apart.

If you want to get pregnant, then engage in as much consensual penile-vaginal intercourse as you can while being postpubescent and premenopausal.

If you do this, there is an 85% chance you will get pregnant within one year.

For the other 99.9996% of times you are engaged in penile-vaginal intercourse; that is, the times you do not want to get pregnant, you will want to know about contraceptives. …

For two reasons, you should be regularly doing testicular self-examinations.

The most common malignant cancer for adolescent boys is testicular cancer. In fact, testicular cancer is the most common form of cancer for men less than 40 years of age. One out of every 250 boys and men will develop testicular cancer; and one out of every 5000 of those diagnosed with testicular cancer will die from it.

When detected early, testicular cancer has a variety of treatments which yield survival rates greater than 90%.

Thus, physicians recommend men regularly doing testicular self-examinations.

Before doing your self-examination, keep in mind…

Most people believe in sexual myths (Nobre & Pinto-Gouveia, 2006; Williams, 1990) — for example, “a woman’s hymen determines her virginity.” Believing in sexual myths often leads to sexual prejudices and discrimination. As a replication and extension of Lucas, Fox, et al., 2019 — who found science-based sex education decreases the chances of a person believing in sexual myths, the present experiment tested if science-based sex education decreases the chances of sexual prejudices and sexually discriminatory behavior from occurring.


86 students (mean age of 24.6 years, SD = 6.5) from three different colleges taking human sexuality courses (Higher Education…


Although often publicly presented as a simple, binary (yes or no) phenomenon (Withers, 2019), science is revealing sexual consent to be complex and variable. Part of sexual consent’s complexity is it depending on such factors as gender, relationship status, and types of sexual behavior (Willis et al., 2019). Using a novel, non-binary measure, the present study tested whether people’s judgments of sexual consent depend on biological sex and sexual orientation.


Two-hundred-sixteen freshmen- and sophomore-level college students with a mean age of 21 years (SD = 4.5) served as experimental participants; sixty-three percent identified themselves as women.

Following informed…

Except for premature ejaculation, men suffer from erectile dysfunction (ED) more than any other sexual dysfunction. ED is not a disease specifically caused by aging, nor is it an “old man’s disease.” It affects about 10 percent of men per decade of life; that is, 20 percent of men in their 20s, 40 percent of men in their 40s, 70 percent of men in their 70s, etc. And recent demography studies are reporting greater numbers of younger men having ED. For example, a 2018 poll of 2,000 men found the largest affected age group were those in their 30s, with…

Don Lucas

I am a Professor of Psychology at Northwest Vista College in San Antonio Texas. My research focus is human sexuality. I also host a YouTube channel, 5MIweekly.

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