Generally speaking, a temporary or fixed term contract has no special status in law, and if you are an employee, you will have all the rights of a permanent employee. In fact, it is unlawful to treat fixed term workers less favourably than permanent workers. You have all the maternity and health and safety rights of ordinary employees.
If you are on a fixed term contract which is not renewed, it is still a dismissal under law, and has the potential to be an unfair dismissal, depending on the circumstances.
If your contract ends and is not renewed, you need to look at the reasons why. If there is no longer a need for you to do the work, for example because the project has ended, you are redundant, and if you have two years’ continuous service with the employer you will be entitled to a redundancy payment. If this happens while you are on maternity leave, you have some special rights.
If the job still exists, and your contract is not renewed because of your pregnancy or maternity leave, the dismissal will be discriminatory and automatically unfair. A woman who is dismissed while pregnant must be given written reasons for her dismissal.
It is automatically unfair to dismiss a woman because she is pregnant or intends to take maternity leave even if this means that she is unable to work for the majority of the contract, whether because of maternity leave or because of health and safety reasons.