Stefanidou began her career as a journalist, working for Hellenic Broadcasting Corporation. Later, she co-hosted ANT1's morning show Kalimera Ellada with Giorgos Papadakis and was a newscaster on the same TV station for a period. She has worked for Alpha TV, Tempo TV, Alter Channel and ANT1, presenting tabloid talk shows, like Alter's Yialinos Toichos (2001), Fyllo ke Ftero (2002) and Me to Ganti (2003), and ANT1's Apoklistika (2004) and Apokalypsi Tora (2005). All these shows, have had mediocre ratings due to their overly scandalous topics. Perhaps the most notorious topic was digging the garbage of celebrities and then commenting on the cost of the products which were found in it.
From September 2006 to June 2010, Stefanidou hosted the talk show Axizei Na to Deis, which aired on ANT1.
She has also hosted ANT1's Fame Story and Big Brother reality shows and has, twice, been the presenter of ANT1's Star Hellas beauty pageants in 2005 and 2006, something which provoked doubts as to whether she is a journalist or TV host.
Stefanidou got married in 1995 to businessman Panayiotis Stavropoulos, but the marriage ended in a divorce in 2002. While married to Stavropoulos, she met a rising TV persona, Nikos Evaggelatos, whom she married in 2003. She has two children: a son named Nikolas (born 1999) and a daughter named Lydia (born 2004).
- http://www.star.gr/index.php?ID=media&Rec_ID=54562 Συμφώνησε η Τατιάνα με το STAR (in Greek)