i was told during maternity leave that i'm fired because my position is filled by someone and they don't have any silimar position open. i worked for this large company for less than one year, and i understand FMLA requests 1 year of service. but the company's handbook says" no eligibility requirements for pregnancy disability leave, all employees are eligible without regard to length of service" and "if an employee returns within the 4 month period, the employee must be given her previous position unless this would cause the company undue hardship". before i taking maternity leave, my boss and HR promised me the position will be held for me if i return within 6 weeks, and nobody ever mentioned to me that i may not get my job back. however, like any large company, the handbook is well writen and mentioned "the contents of this manual may be changed without notice and consent from you" and "this reference guide is not intended to create any legally binding obligation". dose this mean they can break their promises freely only to the reap of their benefit? any resource can protect me in this case?

The question here is what they would do for a similarly situation employee who was on a non-maternity medical leave of similar length.

You are correct that since FMLA does not apply, they are not obligated under the law to return you to work. You are also correct that since the handbooks specifically states that the handbook can be changed or amended, they are not bound by the promise to return you to work.

However, both Federal and NJ law requires that pregnancy must be treated exactly the same as any other medical condition. You can't be discriminated against; you don't get any special privileges.

So if a similarly situated employee who had a broken leg or pneumonia would have their job held for them, yours has to be held for you. If the hypothetical other employee would also lose their job, you can lose your job.

thank you, cbg.
there was an employee from another department who's employed less than 1yr and took around 2 month maternity leave last year and she returned back to her position. can this be considered 'similar situation'? but she left the company and i donot have any contact with her to confirm the case.

Since she also took maternity leave, you would be similarly situated but at the same time the fact that they did restore her to her former position makes it hard to claim they discriminated against you for taking maternity leave. Both of you took leave for the same reason so the reason couldn't be the determining factor. More likely they determined they couldn't afford to hold your job open and that wasn't a problem for hers for whatever reason.