J.L.
You need to keep a separate log-not accessible by anyone at work and begin documenting every incident that is happening to you. Whatever you do DO NOT QUIT-they will win. Request that your manager give you a copy of your employee work file and your job description, also if you no longer have it obtain a copy of your employee handbook. Spend some time reviewing the job description you were hired at vs. the work load they are giving you. Also request a copy of the specific rules regarding the test that you are to take. Now the next step is critical for your case. Submit all your requests in WRITING and keep a copy on your computer at work and send duplicates to you home computer as back up.
You may still request things verbally and have conversation; however, send a letter summing up the conversation every time if your boss/upper management does not provide you with written instructions/answers.
For instance send a letter to whomever you recently spoke to about receiving the additional study materials and sum up the conversation you had as truthfully and tactfully as possible, then submit the copy of the rules and regulation for the test and any relating material from the handbook and make your request again AND politely ask if there is a particular reason you are not being provided this material and remind them that you have received permission to take the test in August because your original date fell into your maternity leave. End with reaffirming your dedication to the job and desire to perform to the company's expectations.
Next, after you have compiled your documentation and begun backing up all your conversations in writing you have a powerful asset in protection your job. As effective as the EEOC may be I would also contact the Illinois Department of Labor for advice.
Just make sure you get everything documented as soon as possible-keep your notes brief and free from emotional wording-this way if you can show that your job expectations significantly changed since your pregnancy and you began receiving poor reviews or possible termination because of the new expectations you will have a trail of paper that will be able to dispute claims of poor job performance. You will also have documentation showing your dedication to the job and your willingness to do all that they are asking, within the constraints of your original job description.
It is likely that once you begin documenting and responding by written correspondence in which you remind your boss how dedicated you are to the job things will most likely change for the positive without you having to file any further claims. But if you do pursue any claim I would sit down with your boss and explain what you are doing and why and let him/her know that it is mainly because you want to protect your job and you are sorry if your claim puts him/her in an uncomfortable position.
Don't be surprised if things change immediately, a good supervisor who wants to keep their own job will do whatever it takes to keep a black mark like that showing up on their record. Also it will prove what you are saying that you just want to keep your job and do it well.
Lots of employers make lots of mistakes and mistreat employees and most get away with it because people are afraid to have the confrontation, they'd rather find work elsewhere, but in this economy employees need to protect their jobs, because there are no other jobs. Don't give up, be diligent and honest in your record keeping and keep open communication going between everyone. Also in your employee handbook there is probably a grievance procedure listed-I would utilize that as well, if necessary.
hang in there, it will be well.