If a baby in womb is able to grow in size, responding to stimuli but it is not conciousness which is a characteristic of a living ones,then how can we categorise a baby in womb as a living?

Living:Livingthings use energy within their cells. This energy powers all kinds of processes, such as reproduction, growth, or body temperature regulation. ... The complex relationships between manyorganismsin an environment allow for energy to be passed between them.Living organismsalso grow and develop.

A baby is living. because It performs all the actions that fall under the criteria to be called living.

Consciousness: the state of being aware of and responsive to one's surroundings.
It is proved scientifically that a baby in the womb will respond to every stimulus.

Eg., Ears:Yourbaby'sears begin to form around eight weeks and become structurally complete at about 24 weeks. Thanks to the magic of ultrasound and other high-tech tools, researchers have discovered that yourbabyis living in an auditory playground,respondingto voices and othersoundsthey hear outside of thewomb.

So, technically zygote is a single living cell from which the entire baby is formed.