According to Official Guinness Records,
The most marathons run in one year by a female is 168 and was achieved by Parvaneh Moayedi (Iran) between 11 November 2012 and 10 November 2013.
Parvaneh began her attempt on 11 November 2012 at the Rock 'n' Roll San Antonio Marathon in San Antonio, Texas, USA, and completed the last of her marathons at the Fort Worth Marathon in Fort Worth, Texas, USA, on 10 November 2013.
For a complete list of 2013 records, please visit 2013 Guinness Records in United States.