the estrogen act as stimulus for replacement of columnar cells by squamous cells (Squamous metaplasia) and this will lead to move the transformation zone inward (towards endocervix) then how it moves outward in response to estrogen?
Original squamo coloumnar junction lies at external OS
At puberty
Estrogen is released from HPO axis
Acts on coloumnar cells & increased glycogen content on squamous cell
Lactobacilli /Dodulein bacilli acts on glycogen produce acidic pH
The acidic PH acts as a stimulus for aquamous metaplasia