In our case, HR informs me confidentially when an employee is an "expectant mother " or returning to work as a "nursing mother" and that triggers a specific Health & Safety check/assessment etc. I do not get involved and in fact do not want to be involved in "how" HR in informed. In our case, on becoming pregnant, employees colleagues are advised to notify their line manager as soon as possible, primarily for health and safety considerations. ( in any case, the risk assessments should have taken this into account) However, by the end of the 15th week before the expected week of childbirth, employees are required to inform in writing to HR of: (a) the fact that they are pregnant (b) their expected week of childbirth (c) the date on which they intend to start their maternity leave. Employees must provide a MATB1 form but that us normally issued around 26 weeks