Simple definition of Sanskar is
“Sanskaro hi gunaantaradhanam“
To replace bad qualities by good ones. Simply we can state as making changes. So now here we are going to make good & positive transformation. We can understand the concept by a simple example. When we add small quantity of curd in milk, milk loses its nature (Prakruti) and is altered to curd which is a unnatural form (Vikruti), but further when we blend / beat this curd, it further changes properties to form butter and buttermilk which are still unstable. After heating this butter we get a last stable derivative i.e. ghee, which bears good qualities enhancing with time. From this we can illustrate that replacement of quality depends on the type of Sanskar (reformation). Garbha means the inner most part, here the fetus which is maturing in mother’s womb.
Jointly Garbha + Sanskar means reforming, polishing, finishing, molding & educating the unborn.
So Garbhasanskar can be defined as evolving a civilized, cultured, decorative, purified, Impressible, Sensitive but still physically, mentally, emotionally, spiritually stable population.