Our natural lashes regenerate every 8 weeks, however each lash is not always in the same phase of growth. For example, extensions applied to lashes in the final Telogen stage will shed sooner than extensions applied to lashes in the Anagen or Catagen stage of growth. Your lash artist may not apply extensions to the shorter lashes in order to protect the health of your natural lashes. Your natural lash must be at least half the length of the extension in order to support it. Your artist will always recommend a length that your natural lash can support.

Each eye sheds 2-5 natural lashes per day.

In 1 week we will lose approx. 40 lashes.
In 2 weeks we will lose approx. 80 lashes.
In 3 weeks we will lose approx. 120 lashes. 

Fills are recommended every 2-3 weeks. 
After 3 weeks the extensions that are left tend to be very grown out, which can cause them to twist. Full sets are recommended after 4 weeks.

The Lash Growth Cycle