Bihar has a sex ratio of 916 which stands 25th among 35 states and union territories as per the latest census reports. There is a declining figure of 3 points from the census of 2001. In the year of 1901, the sex ratio of Bihar was 1,061 which are leading Kerala and Goa with 57 points.
The decline in sex ratio is because of the age old practices followed by the people of bihar. Female infanticide is one of the major reasons for decline in sex ratio in bihar. People of india are becoming more and more open minded and even bihar should not fall back to give up such unethical and irrational practices so that even it could also contribute equally to the nation's advancement.
Yes you are right that the age old practice followed by the people of Bihar is the main cause of the loss of girl child. Sex ratio is less i guess not only in bihar but almost all the poor states such as rajasthan, jharkhand where there is poverty, people usually find it hard to brought up the girl child and hence they kill it inside the womb, o matter if it is a crime against law.