What notice of their intention to take maternity leave are employees required to give?

An employee must notify their employer that they are pregnant, of the expected week of childbirth (EWC) and of the date on which they wish to start their maternity leave. The employee must provide this information by the end of the 15th week before their EWC. They have the right to change their mind about the date on which they want their maternity leave to begin, but must notify the employer of the revised start date at least 28 days before the day in question.