She was born on 18. May 1966 in Otwock, Mazowieckie, Poland. She participated in the 1992 and 1996 Summer Olympics. Her personal long jump record is 6.96 meter set in 1994. In Denmark Pytelewska Nielsen was associated with the club Århus 1900 and she won most Danish golds in long jumps between 1990 and 2001. In Denmark she also participated in 60 metres, 100 metres and triple jump.
In 1983 as Renata Pytelewska she met Lars Nielsen, a Danish pole vaulter. She moved to Denmark and in 1988 she gave birth to their twins. She got Danish citizenship in 1992.