I've read several studies about how testosterone levels are affected by environment/relationships/etc. I compiled the most interesting results and was wondering your opinions?

-Falling in love decreases men's testosterone levels while increasing women's testosterone levels. There has been speculation that these changes in testosterone result in the temporary reduction of differences in behavior between the sexes.

-It is suggested that after the "honeymoon phase" ends—about one to three years into a relationship—this change in testosterone levels is no longer apparent.

-Fatherhood also decreases testosterone levels in men, suggesting that the resulting emotional and behavioral changes promote paternal care.

-Men who produce less testosterone are more likely to be in a relationship and/or married, and men who produce more testosterone are more likely to divorce.

-Single men who have not had relationship experience have lower testosterone levels than single men with experience. It is suggested that these single men with prior experience are in a more competitive state than their non-experienced counterparts.

-Men who produce more testosterone are more likely to engage in extramarital sex.

-Testosterone levels do not rely on physical presence of a partner for men engaging in relationships (same-city vs. long-distance), men have similar testosterone levels across the board.

-Physical presence may be required for women who are in relationships for the testosterone–partner interaction, where same-city partnered women have lower testosterone levels than long-distance partnered women.

-It has been found that when testosterone and endorphins in ejaculated semen meet the cervical wall after sexual intercourse, females receive a spike in testosterone, endorphin, and oxytocin levels, and males after orgasm during copulation experience an increase in endorphins and a marked increase in oxytocin levels. This adds to the hospitable physiological environment in the female internal reproductive tract for conceiving, and later for nurturing the conceptus in the pre-embryonic stages, and stimulates feelings of love, desire, and paternal care in the male (this is the only time male oxytocin levels rival a female's).

I have sources if there is an interest.

**SOURCES: http://www.psyneuen-journal.com/article/S0306-4530(03)00161-6/abstract http://www.mayoclinicproceedings.org/article/S0025-6196(11)62407-5/abstract http://sf.oxfordjournals.org/content/72/2/463http://sf.oxfordjournals.org/content/72/2/463 http://sf.oxfordjournals.org/content/77/1/315 http://link.springer.com/article/10.1007%2Fs12110-004-1016-6 http://www.sciencedirect.com/science/article/pii/S0018506X06003321 http://joe.endocrinology-journals.org/content/52/1/51 http://www.sciencedirect.com/science/article/pii/S0018506X09001056 http://www.sciencedirect.com/science/article/pii/S0018506X10002503 http://www.sciencedirect.com/science/article/pii/S0018506X06001267 http://www.sciencedirect.com/science/article/pii/S0018506X01916964

A lot of them you have to pay for to see the full study (Sorry I get them through work)