LONDON (AP) - Prince William's wife, Kate, was admitted to the hospital in the early stages of labor on Monday, palace officials said.
Royal officials said that Kate travelled by car to St. Mary's Hospital in central London with Prince William. Kate - also known as the Duchess of Cambridge - is expected to give birth in the private Lindo Wing of the hospital, where Princess Diana gave birth to William and his younger brother, Prince Harry. She will be looked after by a top-notch medical team led by royal gynecologist Dr. Marcus Setchell.
Kate and William, who spent the weekend at Kensington Palace, traveled to the hospital without a police escort just before 6 a.m., their spokesman said.
"Things are progressing as normal," he added.
The baby will be third in line for the British throne, and should eventually succeed grandfather Charles and father William as king or queen of Britain and 15 other countries including Canada and Australia.
But little else is known about the eagerly awaited royal baby, from how it will arrive to its gender or its name.
Kate - formally known as the Duchess of Cambridge - is expected to deliver in the Lindo Wing, where Princess Diana gave birth to William and his younger brother, Prince Harry. It is not clear if she will have a natural birth or deliver by a planned cesarean section.
Royal watchers must wait to be told of the baby's arrival from the palace, which is planning to reveal the news through a mixture of tradition and social media.
Palace officials have said that the first hint will come when a royal aide emerges from the hospital with a signed bulletin carrying the Buckingham Palace letterhead. The bulletin will be given to an official who will be driven to Buckingham Palace, where it will be posted on an easel in public view in front of the building.
At the same time the bulletin is posted, there will be an official announcement on Twitter and the media will be formally notified. The document will give the baby's gender, weight and time of birth.
It could be some time before the baby's name is made public. When William was born, a week passed before his name was announced. Charles's name remained a mystery for an entire month.
But it is the baby's gender that is of particular interest because the prospect of Kate's pregnancy prompted a change to laws of succession to ensure a daughter would not be passed over for the crown by a younger brother. Boy or girl, the child will be third in line to the throne and the prospective future monarch.
The birth of a new heir to the throne has been breathlessly anticipated since William and Kate wed on April 29, 2011, in a lavish ceremony at Westminster Abbey.
When news of a royal pregnancy was announced, there was rejoicing in many households in Britain and throughout the world.
Despite a rough start to the pregnancy, when she was hospitalized for acute morning sickness, the 31-year-old Kate made a number of public appearances that were halted only near the end of her term.
Since the duchess has cut back on her royal duties, media outlets have been clamoring for position outside of the hospital in anticipation of the birth, jockeying to secure the best vantage point for filming William and Kate emerging, babe in arms.
Officials have said that William plans to take two weeks' paternity leave and then return to his military duties as a search-and-rescue helicopter pilot in Wales.
His tour of duty is scheduled to wrap up around September, and he and Kate are expected to move from their isolated cottage on the island of Anglesey off the coast of Wales to Kensington Palace in central London.
But major refurbishment works at the palace likely won't be finished until at least a month or two after the infant is born - meaning that William and Kate will most likely have to make do with their current temporary home in London, a two-bedroom property at the palace.
Come autumn, however, the family will be able to move into their permanent London home, Apartment 1a at Kensington Palace - a four-story house with a nursery, 20 rooms and a private garden.
Here are some highlights of their lives and of the royal pregnancy:
-Sept. 2001: Prince William and Kate Middleton meet at St Andrews University in Scotland where they are both studying art history.
-Christmas 2003: The pair reportedly become a couple after sharing a house together with two friends. In March they are pictured together on a skiing holiday in Switzerland.
-Nov. 16, 2010: William and Kate's engagement is announced by Clarence House officials. The prince proposed to Kate while on a private holiday to Kenya the previous month.
-April 29, 2011: The pair wed in a lavish ceremony at London's Westminster Abbey. William is made the Duke of Cambridge by his grandmother, Queen Elizabeth II, and Kate becomes the Duchess of Cambridge.
-Dec. 3, 2012: The palace announces that Kate is pregnant and being treated in hospital for acute morning sickness. Kate is discharged from the hospital after three nights, telling reporters she is feeling "much better." The palace later announces that the bay is due in July.
-Feb. 5: The couple holiday on the Caribbean island of Mustique with Kate's parents.
-March 5: Kate apparently lets slip that she is expecting a daughter on a solo visit to Grimsby. Accepting a teddy bear from a member of the public, she apparently replies: "Oh, is this for our d...? Thank you so much." The possible slip of the tongue prompts a wave of betting on a royal daughter.
-March 17: Kate tells a soldier at a St Patrick's Day parade that they do not know the sex of the child, but says she would like a boy and William a girl.
-March 20: Kate given a "Baby on board" badge when she joins the Queen and Prince Philip at Baker Street underground station to mark the 150th anniversary of the Tube.
-May 11: Kate and William attend William van Cutsem and Rosie Ruck Keene's wedding in Oxfordshire, England. The pair reportedly take to the dance floor despite Kate being seven months pregnant.
-June 4: William and Kate return to their wedding venue at Westminster Abbey when they join the royal family for a service marking the 60th anniversary of the Queen's Coronation at Westminster Abbey.
-June 13: Kate carries out her final solo engagement before going on maternity leave when she names a new cruise liner - the Royal Princess - in Southampton.
-June 15: The Duchess makes her last scheduled public appearance before the birth at the Trooping the Color parade.
-June 19: It is confirmed Kate is planning to give birth at the private Lindo Wing of St. Mary's Hospital in Paddington, where Princess Diana gave birth to William and Prince Harry. It is reported Kate is hoping for a natural birth.
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