I've heard every 4 sec and 7 sec a baby is born. does anyone know?
The estimates you have heard are wrong by at least an order of magnitude.
The world's population is currently increasing at a rate of one person roughly every 0.4 seconds. Bearing in mind that some people are dying, this means that there must be more than one birth every 0.4 seconds.
Best wishes - Majikthise.
I heard now its every 3.4 seconds.....hmm.....eh.
one baby is born every 4.2 seconds ... :)
every minute 1 baby or more
Once every marvin. Marvin