Learn how to say Prematureness correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word premature:
occurring or done before the usual or proper time; too early:
the sun can cause premature ageing
it would be premature to draw any firm conclusions at this stage
(of a baby) born before the end of the full term of gestation, especially three or more weeks before:
the child was three weeks premature
late Middle English (in the sense ‘ripe, mature’): from Latin praematurus ‘very early’, from prae ‘before’ + maturus ‘ripe’