With apologies to Joeprah. :P

Since history was recorded, male human beings have built whole cultures around the idea that penis-envy is “natural” to women - -though having such an unprotected organ might be said to make men more vulnerable, and the power to give birth makes womb-envy at least logical. In short, logic has nothing to do with it. What would happen, for instance, if suddenly, magically, men could menstruate and women could not? The answer is clear - menstruation would become an enviable, boast-worthy, masculine event:
Men would brag about how long and how much.
Boys would mark the onset of menses, that longed-for proof of manhood, with religious ritual and stag parties.
The US Congress would fund a National Institute of Dysmenorrhea to help stamp out monthly discomforts.
Sanitary supplies would be federally funded and free. (Of course, some men would still pay for the prestige of commercial brands such as John Wayne Tampons, Muhammed Ali’s Rope-a-dope Pads, Joe Namath Jock Shields - “For Those Light Bachelor Days,” and Robert “Baretta” Blake Maxi-Pads.)
Military men, right-wing politicians, and religious fundamentalists would cite menstruation (”MENstruation”) as proof that only men could serve in the army (”You have to give blood to take blood”), occupy political office (”Can women be aggresive without that steadfast cycle governed by the planet Mars?”), be priests and ministers (”how could a woman give her blood for our sins”), or rabbis (”Without the monthly loss of impurities, women remain unclean”).
Male radicals, left-wing politicians, and mystics, however, would insist that women are equal, just different; and that any woman could enter their ranks if only she were willing to self-inflict a major wound every month (”You MUST give blood for the revolution”), recognize the preeminence of menstrual issues, or subordinate her selfness to all men in their Cycle of Enlightenment.
Street guys would brag (”I’m a three-pad man”) or answer praise from a buddy (”Man, you are lookin’ good”) by giving fives and saying, Yeah, man, I’m on the rag!”
TV shows would treat the subject at length. * “Happy Days”: Richie and Potsie try to convince Fonzie that he is still “The Fonz,” though he has missed two periods in a row. * So would newspapers.(JUDGE CITES MONTHLY STRESS IN PARDONING RAPIST.) * And movies. (Newman and Redford in “Blood Brothers”!)
Men would convince women that intercourse was more pleasurable at “that time of the month.” Lesbians would be said to fear blood and therefore life itself - though probably only because they needed a good menstruating man.
Of course, male intellectuals would offer the most moral and logical arguements. How could a woman master any discipline that demanded a sense of time, space, mathematics, or measurement, for instance, without that in-built gift for measuring the cycles of the moon and planets - and thus for measuring anything at all? In the rarefied fields of philosophy and religion, could women compensate for missing the rhythm of the universe? Or for their lack of symbolic death-and-resurrection every month?

(Source)