The killing of baby girls in Eastern culture is a throwback to a long distant past started in India by the Brahmins.
The Hindus carried out girl baby killings to an extreme in their past. So much so that parts of India had a 10:1 ratio of men to women. This caused incredible fighting between the men for the few women available.
If anyone would like to check it out, here's some links to a quite long book (Genocide of Women in Hinduism by Sita Agarwal) describing it:
http://www.geocities.com/realitywithbite/hindu.htmhttp://www.womensweb.ca/k2news/example1.php?Action=Full&NewsID=53