All human genitalia develop from the same embryonic tissue. At eight weeks gestation the physical parts are almost identical, appearing primarily female at this point. There is a large glans at the superior aspect of the tissue. This becomes the clitoris in females (shrinking and becoming surrounded by the labia) and becomes the glans penis in men.

Below this there is an open vertical urethral fold and urogential groove, surrounded by a lateral buttress. Below the urethral groove is the anal tubercle. In females these tissues do not change much throughout gestation.

The urethral fold and groove widen and flatten slightly to form the inner labia and opening to the vagina. In men these tissues fuse (from bottom to top) forming the urethra and the shaft of the penis (the buttress). On each side of the urethral folds are round bodies of tissue called labio-scrotal swellings.

In women these flatten and spread to form the labia majora. In men these buttresses fuse in the midline, and widen, creating the scrotum, maintaining a canal into the peritoneum (the inguinal canal) through which the testes can descend. Even the testes and ovaries arise from identical undifferentiated gonadal tissue. We are made of the same stuff.

The driving force in transforming these mostly female tissues into male genitalia is the presence of functional, hormone secreting, testes.

In the absence of testicular hormones the fetus will develop female (external) genitalia. There are, of course, many factors that can lead to a disruption in this process (androgen insensitivity, congenital adrenal hyperplasia, androgen maternal tumors, etc.) and may result in a baby being born with ambiguous genitalia

Although the culturally-based stimuli that result in a state of arousal in women and men are often quite different, the physiological reactions to arousal are similar. There is a localized (and generalized) relaxation of vascular smooth muscles resulting in an increase in blood flow to the genitalia. This generally results in increased vaginal lubrication, and tissue swelling and reddening, in females, and often though not always may result in erection in males.

Throughout the full spectrum of gender, there tends to be an increase in tactile sensitivity associated with increased blood flow. As erotic stimulation is transmitted to the brain via sensory neurons, the autonomic centers of the brain (the limbic system, the hypothalamus) begin to arouse as well, entering into a peripheral-to-central-to-peripheral nervous system feedback loop.

Doc-

Doc, thanks very much for sharing this information!

It was my awareness of these facts back in 1993 that gave me hope, motivation, and some clues for discovering an authentic alternative to ejaculation blocking as the "only" way for men to experience multiple orgasms.

Fortunately, it was my awareness of these fundamental neurological similarities across the spectrum of gender that led me to developing a method, the Multiple Orgasm Trigger Protocol, which turns out to be equally effective for men and women.

Thanks again Doc for articulating the neurophysiology so clearly!

Best regards,
Jack

[Readers: For a more detailed account of how I made the discovery, please see Chat Transcript 0038 in the Multiple Orgasm Trigger Discussion Forum conference titled: "Chat Transcripts of all past coaching chats."]