Rothery was born in Vancouver, British Columbia. She started her career when she played in the musical Bye Bye Birdie at the age of thirteen, and knew that she belonged in front of the camera when she played in the CBC Halloween special Boo at the age of eighteen.
She is best known for her role as Dr. Janet Fraiser on Stargate SG-1 which she played from the show's beginning in 1997 through 2004 (and again as a guest appearance in 2006). She has also appeared on many other sci-fi series, including The X-Files, The Outer Limits, First Wave, Jeremiah, M.A.N.T.I.S., Kyle XY, Eureka and many others. She played a small role in the Babylon 5 direct-to-DVD movie Voices in the Dark as an ISN Reporter, mentioned only as Ms. Chambers. She played Lenore Molee in the 1994 TV movie For the Love of Nancy, and she has also done voice acting work. In 2010, she was on the Battlestar Galactica spin-off prequel Caprica as Evelyn, the eventual mother of Battlestar Galactica's Admiral William Adama.
Most recently she has been acting on theatre in her native Vancouver—appearing in Kiss Me, Kate and The Taming of the Shrew in March 2006. In March 2007 she appeared in A Delicate Balance by Edward Albee, a role for which she was nominated for a Jessie Richardson Theatre Award.
Rothery has been nominated for four Leo Awards. In 2004 she was nominated in two categories: Best Supporting Performance by a Female in a Dramatic Series for the Stargate SG-1 episode "Lifeboat", and Best Guest Performance by a Female in a Dramatic Series on The Collector. In 2008 she was nominated in the category: Best Performance by a Female in a Short Drama for her work in the short film Coffee Diva.In 2009 she was nominated in the category: Best Supporting Performance by a Female in a Dramatic Series for the episode "Sound of Loneliness" from The Guard. In 2011 she played Mrs. Turner in "A Fairly Odd Movie: Grow Up, Timmy Turner!", and reprised the roles in the sequels "A Fairly Odd Christmas" and "A Fairly Odd Summer".
|1986||Project A-ko||Eiko "A-ko" Magami||Magami in the English dubbed movie and OAV series.|
|1987||Ranma ½||Kodachi Kuno||Voice in English dubbed version until 5th seasion.|
|1992||Mortal Sins||Lena Falcone|
|1993||Exosquad||Lt. Maggie Weston||1993–1995|
|1995||Dragon Ball||Mai||Early 13 episode 1995 English dub.|
|1996||Dragon Ball: Curse of the Blood Rubies||Raven|
|1996||The Outer Limits||Janet Peston, Dr. Lucy Cole|
|1997||Stargate SG-1||Janet Fraiser||Seasons 1-7|
|1997||Warriors of Virtue||Kathryn Jeffers|
|2001||Help! I'm a Fish aka A Fish Tale||Mother|
|2003||G.I. Joe: Spy Troops||Baroness||Voice|
|2004||Dead Like Me||Linda the Realtor||3 episodes|
|2004||G.I. Joe: Valor vs. Venom||Baroness||Voice|
|2005||The Sandlot 2||Mrs. Goodfairer|
|2006||Kyle XY||Carol Bloom||2006–2009|
|2006||Barbie: Mermaidia||Pink Merfairy|
|2007||Babylon 5: The Lost Tales||Ms. Chambers|
|2007||Eureka||Diane Lancaster||1 episode|
|2009||Good Boys and True||Elizabeth Hardy||By Roberto Aguirre-Sacasa at the Firehall Arts Centre in Vancouver; September 9-19|
|2009||Street Fighter IV||Rose|
|2010||Hellcats||Mrs. Monroe||Episode: "I Say a Little Prayer"|
|2010||Battle of the Bulbs||Mary Jones|
|2011||A Fairly Odd Movie: Grow Up, Timmy Turner!||Mrs. Turner|
|2012||A Fairly Odd Christmas||Mrs. Turner|
|2014||A Fairly Odd Summer||Mrs. Turner|
Fairly Odd Movie
Teryl plays Mrs. Turner in A Fairly Odd Movie: Grow Up, Timmy Turner!.She has been seen smiling happily alongside her husband at their now son 23-year old son Timmy, until he reveals that he wants to live with them forever. At some point of the movie, her and her husband are seen "vacationing" outside their house until Denzel Crocker falls from the sky in front of them.