Today's visit is the last official engagement before the royal birth. Kate is expected to have her baby at St Mary's Hospital in London. That is where both William and Harry were born.
But if baby comes early - and the Duchess is at her parents' home in Berkshire, as she says she will be - there could be a dash to the Royal Berkshire Hospital in Reading. They are on the standby - just in case. And that is where Kate herself was born.
Sangeeta was given an exclusive visit to the maternity unit to meet the staff and the new arrivals.