Law / Advice on rights for an unborn child in Poland [23]

HI, I am Indian, visited Poland as a tourist in June and returned back to Indian after a month , i visited my girlfriend house, she is divorced women. she became pregnant and going to delivery on April 3rd 2016. due to some misunderstanding she stopped communicating with me. so please tell how i can get rights on my future son? what are the legal formalities should be done to register me as father to my child.? kindly help me, i have all information about my girl friend.