He blasted the pregnant mother to her face.
I think his concern was, first, medically out-of-date. I trust the woman and her husband were able to weigh up the risks and benefits, and judge for themselves that this was medically appropriate in her situation. Nowadays multiple C-sections are considered high-risk, yes, but not reckless, and are much less hazardous than they were even 25 years ago.
Second, Pope Francis' way of expressing himself was too brusque, perhaps because he was worried for her sake, by what he perceived to be her risks.
But it was not, in my view, "detraction" motivated by a desire to degrade this woman in public. He was worried about her. And he tends to blurt out his reactions unfiltered. I'll bet the woman has forgiven him. I would.