What is birth? A deep thought about relation between Body and Soul.

Every day, millions of humans beings are delivered every day. Consdering every living being, this will cross zillions and zillions or may be uncountable. So what makes this "birth" so important?
Medically, we know if the brain and heart are working then a human is alive else dead. Brain dead is assumed medically dead.

From Aryans scriptures, it is 5 elements which makes a human body and they are
Earth
Air
Fire
Water
Space

In China, they also consider 5 elements:
Earth
Air
Fire
Water
Wood

So, still we can assume that we don't know the exact proportions of mixing these elements to form a typical human. If we know, then we can form a amoeba if not human body initially as now we all now know the complex body structure of human.

Apart from these five elements there should be something which makes the difference between living and dead and that is the key difference which we term as "Soul". This is supposed to be the only object which can bring difference in the state of human bodies.
Object but no characteristics at all or leastways not known to humans.

So a living being can be considered as soul(unidentifiable object) staying in some material. Womens body is the place where all the materials are automatically mixed in proportion to form a baby and then this baby starts absorbing the materials when it comes out in this world to grow but what about the driving part?

Where this is getting into the body? How womens are privileged to put a soul in a body. How a man women encounter brings a new life? Amoeba splits itself to multiply. Earthworm is hermaphrodite. It is all alone powerful enough to bring a new life. So different creatures but many privileged to grab a soul from somewhere.
May be we can consider this as a endless heap from which whenever you require, grab a soul and put into the human builder and a new baby on the way.

We know for sure that the materials decompose and so do bodies. Even, bodies are burnt, buried etc so it finishes but then why there are cases in which babies remember their past. Past life is gone. Body's decomposed then how is this possible. Soul!!
Soul wasn't decomposed. It just moved to some place, may be back to the heap from where it was picked earlier. Why everyone doesn't remember their past life? Humans won't be even 1% of the living beings considering every living being as the set including fish, animals, insects etc. So what is the probablity of a soul of human getting back to human body may be millionth part of 1 and therefore we are not seeing this happening every other day. Soul are just soul there is nothing like human's soul or mosquito soul. Soul is universally common. It's just the body which makes the difference and the lack of communication beteween the bodies. May be the souls are communicating but body isn't grasping. Mind isn't processing and therefore we don't feel anything.

Bodies grow, bodies dissolve, bodies are marvelous. bodies are ugly, soul is same. It's our mind and heart feelings to which we react. People contradicts if they want to listen to heart or mind.

Now, one more is added but the question is how to hear your soul's voice???