Meghan's personal assistant Melissa Touabti also announced in December after a similarly short period of time, just six months.
In the past, Paddy Power has suspended betting on other royal announcements such as Meghan and Harry's engagement and pregnancy, after an insurgence of bets came through that clearly favoured a particular outcome.
It was previously speculated that the baby could be expected as early as March due to the size of Meghan's bump.
There has been no guidance either on where Meghan plans to have her baby.
The couple were on their first joint official engagement of the year, spending the day meeting Birkenhead residents, visiting an organisation supporting women in vulnerable situations and a centre for young people.
The Duke of Sussex, 34, embraced Eliza Morris after seeing her sign "Gingers Unite - I love you Harry" among the crowds this morning.
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Madrid moved into fourth after beating Real Betis 2-1, courtesy of a late Dani Ceballos free kick. Former Real Madrid rival Cristiano Ronaldo is second all-time in La Liga with 311 goals.
Cuba tourist bus crash kills three locals, four foreigners
Two Argentine women, a German woman and a French man were among those killed in the accident on Thursday, Radio Guantanamo said. Twenty-two tourists and 18 Cubans were on board when the driver lost control in wet conditions and careered off the road.
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However, the Arab country's air defense systems have thwarted most of the attacks. Another official told SANA traffic at the airport had not been disrupted.
Initially established in 2011 to support women upon their release from prison, Tomorrow's Women Wirral has since expanded and now offers an extensive range of training courses and workshops for more than 6,000 local women.
The royal pair chatted and laughed with those who braved a freezing winter's day to meet them.
Their first stop was at Birkenhead's Hamilton Square to view a sculpture erected to mark the 100th anniversary of war poet Wilfred Owen's death. They then met local veterans and members of the Birkenhead Institute Old Boys, of which Owen was a member.
In October, she was with the couple on a Pacific tour when she helped rush the duchess out of a solo visit to a market in Fiji, cutting it short because of the crowds and sweltering conditions.