Lalita Sashti is a vrata or fasting observed on Sashti in Shukla Paksha of Bhadrapada Month. In 2012, Lalita Sashti date is September 20. And in some calendars, it is mentioned on 21 September.
Lalita Devi is one of the principal eight sakhis of Srimati Radharani in Vrindavan. Lalita and her assistants incarnate from time to time in the material realm to propagate the topmost mood of serving Radha – Krishna, namely to become a maid-servant of Srimati Radharani.
Lalita Sashti Vrat is also observed as Santan Sashti Puja. Those who keep this fast will be blessed with children. On this day, Lord Shiva, Subramanya Swamy and Skanda Mata are also worshipped.