An employee who is pregnant or on maternity leave can still be made redundant, but there are some additional protections offered by the law.

The first, and rather obvious one, is the protection against discrimination.  Selecting a woman for redundancy because of her pregnancy, maternity leave, or for a reason related to those is unlawful discrimination.  That will result in the dismissal being automatically unfair.

When an employee is on maternity leave, the employer may decide that the business is able to manage without that role being filled.  For example, they might have been able to redistribute the work to other employees without any adverse impact.  However, this does not mean that the employer can simply make that post redundant.  In that scenario, had the woman not taken time off, she would not have been made redundant. It would amount to unlawful discrimination and unfair dismissal.

Selection criteria that that puts a pregnant employee, or one on maternity leave, at a substantial disadvantage compared with others can indirectly discriminate against them.  Taking account of a pregnancy or maternity-related absence when scoring attendance is one example

The law gives special protection to employees on maternity leave when it comes to being offered suitable alternative employment as an alternative to redundancy.  In every redundancy case an employer is obliged consider whether there is suitable alternative role for an employee at risk of redundancy.

For such an employee who is on maternity leave, if there a suitable alternative role, an employer must offer it to them first.  They have priority over other employees.  Failure to do this, as with those other scenarios, can result in a finding of unlawful discrimination and unfair dismissal.