So I have a lot of experience in facilities similar to this. Naturally, I have a couple of gut reactions based on this experience:
It's complete bullshit that they did not know she was pregnant. Complete bullshit. In every caregiving facility, there is usually a nurse or some other highly skilled individual and at some point during the nine months but that lady was pregnant, some caregiver had to mention the physical change of status to the nurse or the nurse, even incidentally, was called to examine that resident. Enlarging of breasts and enlarging, hard belly are, individually or collectively, symptoms that would naturally require further investigation as signs of a serious health risk.
There are a lot of people wondering if this patient was obese and that's how nobody noticed. Unless this person, and I doubt it, but unless this person had some sort of renal failure or other long-term problem which cause unusual levels of water retention, they were, without a doubt, almost certainly way skinnier than your average person. You don't get fat in a bed in a coma for 10 years. You get skinny as fuck.
This is just my hunch, but I am under the impression that the person who likely committed the abuse what either "protected" in that they were a friend, relative or had some other close relationship to management which caused them to turn a blind eye to the situation as it slowly unfolded. I have personally seen people work in a caregiving situation who would not be trusted with a cash till at any other job who were entrusted to be completely alone with people not just needing care, but very vulnerable people who needed care and who could not, through the profound disability of disease, express distress if they were abused. I'm not saying these people abused them. What I am saying is it it's a very common occurrence for shady, grifter type folks to wind up in facility care jobs. These people have poor impulse control and they're trashing their lives in the process of that, who would be surprised if they have similar poor impulse control and bad decision-making at work?
Again, having worked in this field and having worked at some very bad facilities, there is also the very real possibility, though it's still just a possibility, that multiple caregivers were sexually abusing this resident and that the reason why this took so long to come to light is because one or more of those folks was a "protected" individual, as I defined above.