I recommend using your regulator’s fair lending exam manual as a guide for your internal fair lending review. It will likely give you sample questions to use to determine if a spouse’s information was used without cause. And ways you can determine if discrimination may have occurred is a file comparison where you compare originated vs. denials and originated control group vs. originated prohibited basis group and compare the underwriting criteria to determine if the denial or different terms were justifiable. In the case of discrimination against a pregnant person, I would think that would have to be through a note in the file, observation, or reported by the customer.
Again, your regulator’s fair lending exam manual is a good place to start your internal assessment.