So are you telling me that the participants did not know they were receiving an operation that would prevent pregnancy?
It sounds as though this woman believed that her ability to become pregnant was being prevented, temporarily, but not permanently.
I wonder at what point she found out it was permanent. Had she decided to have more kids, and THEN found out, or did someone just look her up, as a member of this group and give her that information to make her angry, even if she didn't want to have any more kids?