No, however she was born able to walk and immediately helped her
mother with the birth of her twin brother Apollo.
Athena was the goddess that was born fully grown. She came out
of her father, Zeus' head fully grown and clothed.
In humans, the baby is considered pre-term (not fully grown) if
it is born prior to 37 weeks gestational age. Most babies will be a
little bigger and healthier though if they continue to grow for
another 3 or 4 weeks before delivery.