The reason for lowered overall height in girls compared with boys is CLOSURE OF EPIPHYSES DUE TO ESTROGEN SECRETION.
The closure of epiphyses makes girls' growth to begin to level off around the age of 12 and 13, while the boys continue to grow until about the age of 17 or 18. Both boys and girls grow at the rate of about 2 inches per year until they reach puberty age.