Mr Harris argued it was time people spoke out for the good of society
A Labour MP has launched a fierce attack on teenage mothers, accusing them of raising a new "underclass".
Writing in his blog, former transport minister Tom Harris described the "army of teenage mothers living off the state" as a "national catastrophe".
The Glasgow South MP admitted his views were controversial but said it was time to stop worrying about hurt feelings.
Last year he was criticised for asking why Britons were "so bloody miserable" despite the economic problems.
Mr Harris began the blog by recounting how when his wife gave birth two years ago there was a young woman, aged about 16, in the same maternity ward.
He described how the woman's father spoke loudly of his pride in his daughter.
"Proud? Proud that his teenage daughter was not only sexually active but was now a mother?" he wrote.
"Proud that any chance of a decent education, followed by a decent job, was now remote at best?
"Proud that she was, in all likelihood, about to embark on a lifetime of depending on benefit handouts for her and her child?"
He said he could no longer pretend that "the army of teenage mothers living off the state is anything other than a national catastrophe".
"Teenage girls shouldn't be having underage sex. Why? Because it's wrong," he continued.
"Teenage girls shouldn't choose to have babies as an alternative to getting an education and a career. Why? Because it's wrong.
"Parents shouldn't teach their children that a lifetime on benefits is attractive or even acceptable. Why? Because it's wrong."
Sue Robertson, director of One Parent Families Scotland, said the comments were an example of the stigmatisation of single parents.
"We are not actually talking about these young parents spending a lifetime on benefits," she said.
"Research has shown that what's effectively happening is that young parents have their children young, the children grow up and then the young parents go back into education and then into employment."
Green MSP Patrick Harvie criticised the MP's views as "loathsome moralising".
"Not a word about sex education. Not a word about the rights of the women Tom is so keen to judge," he added.
"Not a word about the responsibility of men as fathers.
"Not a word about Labour's failure to eradicate poverty or to close the pay gap women still face. Why? Because Mr Harris doesn't have the moral courage for self criticism."
Mr Harris insisted he was not embarking on a moral crusade, but merely wanted to draw attention to something that was having a debilitating effect on society.
He describes his blog, entitled "And Another Thing", as an outlet for opinions, jokes, musings and whimsy.