"Courtesy is Contagious"

If you ever ride the train,
You will have heard this weird refrain:
“When a pregnant person rides,
Please give your seat up, and besides
You’ll be doing your fair share;
Good manners will be everywhere.”
Those words are not exact, of course,
But close enough to their true source,
Which says, “Courtesy is contagious.”
What a message! How outrageous!
Will a public service plea
Change someone, even one degree?
“Gee, that person’s ‘bout to pop –
I’ll let her sit at the next stop!”
And why use “person?” Guarantee,
A pregnant woman’s not P.C.!
Equality must be addressed;
Genetics doesn’t pass the test.
Yet often, in a subway car,
I witness things that seem bizarre;
And one of these that does astound
Is seeing men, some muscle-bound,
In seats, while standing in the aisle,
A pregnant person’s round profile
Juts into the surrounding space:
Chivalry’s lost its embrace.
And oh, to public service guy:
Your message makes no one comply.
It just gives me a headache, so,
Let life retain its status quo.