I have an employee who is pregnant and is now on a weight restriction , which is part of her job description. Do we have to accomodate this restriction. Her job description specifically states that it requires the ability to lift a certain amount of weight.

In most cases pregnancy is not considered a disability under the ADA, so accomodation is not required from that perspective.

However, under the PDA, you cannot treat someone who is pregnant differently than you would treat someone else with a temporary, non-maternity condition. So if you would accomodate that hypothetical person, you must accomodate her as well. If you would not (and can prove it) you needn't.

What is her job description? What weight requirement is listed in description? What is her weight restriction?