Exemption from election duty

My wife is working in a private engg. college and she received orders for election duty on 30th April, 2014. Now she is pregnent and the same reason was mentioned while filling the election duty form, mentioned as that she is not inrested and selected a reason of "Pregnency".

But still she got orders to attend for polling. She asked her college HR pepole to exempt her from her duties. They said that she has to visit local collector office to place the request.

Please help us on this.