Have a look at the Legal Aid website as they have an information sheet on applying for an extraordinary drivers license.
Basically you have to prove to the Magistrate that you need to be able to drive between certain times in the day and that you are not a safety risk to the public.
Ideally you should have a copy of your traffic record (at the very least) and your criminal record. You can apply for your traffic record on the police website or at your local police station.
Although you no doubt look pregnant a letter from your doctor or OB confirming your pregnancy and your need to attend weekly appointments will help your cause as will a letter from someone who knows you well and confirm why you need to drive and speak to your character.
You will only need the license during the week so be prepared that this is all that you will get and limited to between school hours.
You will also need to explain why you lost the points, I assume speeding, which will be a concern for the court so you will have to convince the Magistrate that you will no longer do this.
In country areas you can use the lack of public transport and expense of Taxis to add to your need to drive.