It depends if you are working or not, if you are living at home or living alone..
If you arent working you can get Jobseekers Allowance until you are 29 weeks.
Then at 29 weeks you get income support instead of job seekers allowance.
You are also entitled to the surestart maternity grant within 11 weeks of your due date(£500) (You need to ask for an applicaton form from this from the Jobcentre)
A cheque for £250 Child trust fund account
Healthy start vouchers...
Then when the baby is here you need to get the birth certificate asap, then take it straight to the jobcentre or wherever you go, and then you can claim Child benifit and Child tax credit.