Question

why they would t to kill the girl before taking birth in her mother's womb

Answer 1

its because they want boy instead of girl so that a boy can continue their family and will get income when he'll do the job. according to them only a boy is capable of doing jobs and other works

Answer 2

This thing is very common in India . Boys can do jobs , earn salary and a girl ' s marriage arrangements and the money are the biggest problems of this situation . Girls were not allowed to work in early times . But nowadays girls can do everything that boys can do .
Save the girl child .