The Catholic Church has been a source of immeasurable misery and despair during its whole existence, but the most harm has always caused its wholesale suppression and denial of the normal human sexuality.
Of course Catholic Church is not alone among religions in its denial of human sexuality, but its physical and social power has ensured that is has been able to harass and disturb more efficiently those who do not fit to its sordid interpretation of allowed sexual practices than many other religions.
As we know the list of allowed forms of sex practices is incredibly short in the Catholic world and an incredible amount of quite normal and healthy Catholics end up in direct conflict with that list.
This creates enormous and quite unnecessary mental pressures for people who are indoctrinated to believe in the absolute truth carried the church and who on the other hand in practice inevitably do end outside the extremely limited realm of allowed sexuality.
Ireland has always been a bastion of extreme Catholic dogmatism and it is no surprise that the horror story of today comes from there:

The Guardian.co.uk has the sordid story with the headline:

The Catholic church sold my child

The whole story is here:
http://www.guardian.co.uk/lifeandstyle/2009/sep/19/catholic-church-sold-child

Nun in cloister, 1930; photography by Doris Ulmann

An excerpt from the story by Martin Sixsmith:
“When her pregnancy became obvious, her family had Philomena "put away" with the nuns. After her baby, Anthony, was born, the mother superior threatened Philomena with damnation if ever she breathed a word about her "guilty secret". Terrified, she kept it quiet for more than half a century. "All my life I couldn't tell anyone. We were so browbeaten, it was such a sin. It was an awful thing to have a baby out of wedlock ... Over the years I would say 'I will tell them, I will tell them' but it was so ingrained deep down in my heart that I mustn't tell anybody, that I never did."
I was intrigued to know why the nuns had been so insistent on the importance of silence and secrecy. The answer, almost certainly, lay in what had happened next.
Philomena was one of thousands of Irish women sent to convents in the 1950s and 60s, taken away from their homes and families because the Catholic church said single mothers were moral degenerates who could not be allowed to keep their children.”
Such was the power of the church, and of Archbishop John Charles McQuaid, that the state bowed before its demands, ceding responsibility for the mothers and babies to the nuns. For them it was not only a matter of sin and morality, but one of pounds, shillings and pence."

"Early on in the search I realised that the Irish Catholic hierarchy had been engaged in what amounted to an illicit baby trade. From the end of the second world war until the 1970s, it considered the thousands of souls born in its care to be the church's own property. With or without the agreement of their mothers, it sold them to the highest bidder. Every year, hundreds were shipped off to American couples who paid "donations" (in reality, fees) to the nuns. Few if any checks were made on the suitability of the adopting families – the only condition laid down by Archbishop McQuaid was that they should be practising Catholics."

"The Lost Child of Philomena Lee" by Martin Sixsmith is published by Macmillan. http://www.amazon.co.uk/Lost-Child-Philomena-Lee-Mother/dp/0230744273