Important reason behind the wearing of half saree and saree:-
There are many positive energies and negative ones around us.
Some of it gives harm to our body with heat . So on wearing saree, the garments (cotton ,silk,etc...) Stops the harmful energies from entering our body..Western clothes on wearing gives more heat to the body which affects the human body mainly the uterus of women as the heat and negative energies extra circulates and affect pregnancy.
***"**********Information taken from websource
.