there is good reason to believe that some of them were preformed without conscent

When your linked article talks about "sterilization without approval" they mean approval for state funds from some review committee, not consent from the patient. That she did give:

*“As soon as he found out that I had five kids, he suggested that I look into getting it done. The closer I got to my due date, the more he talked about it,” said Christina Cordero, 34, who spent two years in prison for auto theft. “He made me feel like a bad mother if I didn’t do it.” Cordero, released in 2008 and now living in Upland, Calif., agreed, but she says, “today, I wish I would have never had it done.”

or under extremely unethical coersion despite officially requiring consent at least 30 days before the procedure. In one case consent was allegedly extracted as the woman was giving birth, despite her having multiple times said she does not want the procedure.

In this article "forced sterilization" means that consent was not obtained lawfully. In most cases, per the audit, prison staff recorded signatures from the person who obtained the consent and the patient herself, but failed to ensure one from the physician at the hospital.

This seems more like incompetence than deliberation to me, although that particular case you mentioned (page 23 in the audit) comes very close. The patient did give consent 30 days prior, but changed her mind midway. At the hospital she then got presented with some standard consent form and signed it.