When man menstruates...

One of good difference between men and women is menopause, because men-no-pause.
Men will go on forever and ever and ever.
Of course, on extremely rare occasion, obligates the recognition of the contribution of sildenafil.

Beyond imagination but true.

What about menstruation?
Can men menstruate?
Not technically menstruating.
Nevertheless it is possible to have a medical consultation of primary amenorrhea for boys!
It's the failure for the boys to start male-menstruating or rather called as "manstruation"
The lack of manstrual cycle in the boys causes anxiety and doubts in the parents.
In those places, the extraordinary is the norm. 
But real men do not menstruate.
The business drive for sanitary pads for boys is in actual fact the parasite infection of urinary tract or intestines by Schistosoma haematobium.

Also cleverly known as Schistosomiasis.

In some tropical peoples that work in wet places such as rice fields, most boys pick up Schistosoma, and start the bleeding, about puberty when they start working in the rice fields, and uneducated locals think that it is normal and refer to it as the male equivalent of female menstruation, and call it by their native language word for "menstruation".^[1]

In at least one case, it was reported that a boy in an affected area started work in a factory instead of the rice fields, and so did not pick up Schistosoma, and did not develop the bleeding, and his father took him to a doctor asking for investigation of primary amenorrhoea.

Source: Wikipedia. 

It is not a serious illness, but it will simply make one weaker primarily down with anemia (lack of oxygen carrying agents in blood cells).

Secondly, it will pathetically present with slight shrinkage of penis (dafuq!) and rare symptoms such as yellowish discharge from the penis, excitedness when least expected (This could be potentially positive), and an undescribable odd feeling (potential orgasm?)

This is to be distinguished from genuine menstruation in an anatomically intersex human who has a functioning menstruating womb but external sexual organs which are on the male side of ambiguous in form, or the menstruation experienced by trans men.
Source: Wikipedia.

Schistosoma haematobium's life cycle below.



P.S. It's not cool for men to have menses.
Men's 'bird' never ever require extra pair of 'wings'. 

P.S. Too bad for men. Men can't conveniently go for MC with primary dysmenorrhea.