The problem is that you do have employers wanting to target individual employees and that just because something is illegal doesn't mean it won't happen. An em

The problem is that you do have employers wanting to target individual employees and that just because something is illegal doesn't mean it won't happen. An employer could use this to identify what employees are about to become pregnant and then find reasons to fire them. And given that being fired is likely to change their chance of choosing to become pregnant, it becomes significantly harder to prove this was an illegal targeted attack instead of a justified firing of an employee who was violating policy (and given how policies are written, workplace policies are treated like laws these days where everyone is violating some policies and they are only selectively enforced). Add in that this is most likely to be deployed against lower income people if it is deployed, and that those it is deployed against will be in a very poor condition to fight back (hiring a lawyer right after losing a job isn't something most can afford), you have a nasty discrimination disaster ready to happen (or in reality, ready to be made worse than it currently is).