Although none of the nations had legislated the change as of September, the British Cabinet Office confirmed that this is now the de-facto rule.
Those changes make Kate’s pregnancy all the more significant for the royal family, according to Ingrid Seward, editor-in-chief of Majesty magazine.
‘‘This is the first child who will be an heir to the throne whatever sex they are,’’ she said. ‘‘It’s a new beginning.’’
Graham Smith of anti-monarchy group Republic called Kate’s pregnancy a ‘‘private, personal matter’’ for her and William, saying the flood of media coverage was disproportionate
‘‘We've heard today that our future head of state is on the way. It’s a pretty bizarre way of choosing someone for public office,’’ he said.
On the couple’s tour of Malaysia, Singapore, the Solomon Islands and Tuvalu in September, William reportedly said he hoped he and Kate would have two children.
Associated Press writers Jill Lawless, Paisley Dodds and AP Medical Writer Maria Cheng contributed to this report.