- Baby will be a Cancer if born before 4.54pm today but a Leo if born after
- Diana, Princess of Wales, was also Cancer while Princess Margaret was Leo
- Old wives' tale says full moons cause many women to go into labour
- Duchess of Cambridge's labour coincided with July full moon at 11.16am
The nation is on tenterhooks as we wait to hear whether our future monarch is a girl or a boy but astrologers claim his or her star-sign can provide us with a telling picture of our future monarch.
The timing of the baby's birth today will dictate whether the baby is an emotional Cancer or fiery Leo, astrologers say.
If the child is born before 4.54pm today, it will be a Cancerian, like its father Prince William and grandmother Diana, Princess of Wales.
But if the baby comes later, astrologers say it will be Leo, like its great aunt Princess Margaret, Countess of Snowdon, and Princess Anne.
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Cancer or Leo? Never mind whether it's a boy or girl, astrologers claim the star-sign of Prince William and Kate's baby will have a bigger influence on the type of monarch it will become
The Duchess of Cambridge went into labour at 5.30am this morning - with many suggesting the approaching full moon at 11.16am helped bring on the contractions.
Prince William is with his wife at the private Lindo Wing of St Mary’s Hospital in Paddington, west London, where he himself was born in 1982.
But as the country waits to hear whether Britain has a future king or queen, there was a Twitter frenzy this morning as to whether it would be born a Cancer or a Leo.
Astrologer with The Association of Professional Astrologers International, Deike Begg, says the timing of the baby's birth will play a huge role in their personality type.
Different personality types: Diana, Princess of Wales, pictured left at a Live Aid for Africa concert in 1985, was Cancer, while Princess Margaret, pictured in 1960, was a Leo
She said: 'If the baby is born before 4.54pm they will be a Cancer - like father William. But its moon will be in Capricorn - which is the same star-sign as mother Kate.
'This means the baby will share a lot of the parents' personality traits.
'As a Cancer, the child will be very family oriented like its parents and sensitive. Cancers often appear strong on the outside but are very soft on the inside.
'But with a Capricorn moon it would also be aware of its responsibilities and dependable.'
Traditionally those born under the star-sign of Cancer - generally between June 22nd and July 22nd although the exact dates vary slightly every year - are sensitive, caring, shrewd, family oriented and protective of their loved ones.
Sharing signs: If the baby is born before 4.54pm today it will a Cancerian like father Prince William, pictured left, with a moon in Capricorn - the same star-sign as mother Kate, pictured right
Famous Cancers include South African president Nelson Mandela, Hollywood actors Harrison Ford, Tom Hanks and Tom Cruise, and Edward VIII, who gave up the throne for American divorcee Wallis Simpson.
Prince William, who was born on June 21, is a Cancerian as was his mother Diana, Princess of Wales, whose birthday was July 1.
But while many people will only count the baby as a Leo if it is born tomorrow, Ms Begg says it will technically be a Leo if born after 4.54pm today.
She said: 'A baby chooses when it wants to be born. A Leo is born to be a king.
'A Cancer would not be happy about being in the limelight whereas a Leo enjoys being the centre of attention.
'If the baby is born a Leo it will be more extrovert and confident.'
Typical Leo traits are said to include confidence, ambition, generosity and loyalty.
Waiting game: Members of the world's media gather outside The Lindo Wing as The Duchess Of Cambridge goes into labour at St Mary's Hospital in London today
Famous Leos include Princess Margaret, Madonna, US President Barack Obama and actress Jennifer Lawrence.
But other astrologers claim the baby will have a 'very Cancerian personality' even if it is born Leo as it will be right on the cusp of the sign.
Astrologer Patrick Arundell said the future king or queen would be more conventional if a Cancerian, but more of a ground-breaker if born tomorrow as a Leo.
'Either way, he or she is going to be larger than life, charismatic and glamorous but they will have a very Cancerian personality, whether under the sign of Leo or not, and be sensitive and caring,' Mr Arundell said.
He added: 'If the baby's born today it will have a slightly more conventional and conservative personality, but if it's born tomorrow it will be more groundbreaking and more in tune with modernity.'
Mr Arundell said the baby would also have a lot of 'go-get energy' and star quality.
'Mars and Jupiter are conjunct in Cancer and that will give the baby a tremendous amount of go-get energy and that is already in motion,' he said.
He added: 'Venus and the Sun are also in a magnetic connection which will give the baby a star quality and a sparkling charisma.'
Famous Cancers: Former South African President Nelson Mandela, pictured, actors Tom Hanks and Tom Cruise were all born under the Cancer star-sign
Meanwhile there have been numerous theories as to what caused the Duchess of Cambridge to go into labour - whether it was the full moon, an electrical storm or just conventional 'Baby Mean Time'.
Maternity wards are said to be busier during a full moon, although there is debate in the medical world about whether the moon does encourage women to go into labour.
Mervi Jokinen, of the Royal College of Midwives, said midwives often talk of how the full moon makes for a busy spate of deliveries.
'It's always sort of been an old wives tale saying that the full moon brings women into labour. Midwives usually do say "I'm on call. It's a full moon. I'll be busy tonight",' she said.
'There was a study about 20 years ago at a hospital near the River Thames which is a tidal river and it showed that on the full moon they did have more births.
'The idea is that because the baby is surrounded by water, the time of the full moon and the high tide causes the waters to break. But there's not enough scientific evidence to show it's proven.'
Birth coach Zara de Candole, of Doula UK, said: 'As a doula (birth coach) who has supported many women in labour, there does seem to be some link between labour kick starting and a full moon.'
Extroverts: Madonna, pictured, Barack Obama and Princess Margaret were all born under the star-sign Leo
There are also suggestions electrical storms and a drop in barometric pressure can bring on labour.
Western central London - near where William and Kate's Kensington Palace apartment is based - experienced isolated heavy rain, thunder and lightning strikes at 6am this morning - just at Kate was admitted to the Lindo wing of St Mary's Hospital in Paddington.
Chris Burton, a forecaster with MeteoGroup, the weather division of the Press Association, said: 'The storm affected western central London. There were lightning strikes at around 6am and very localised, intense heavy rain and thunder.
'We've had high pressure with the sunshine but now there's low pressure and it's hot and humid which can cause thunder storms.'
Mervi Jokinen said she had not seen a connection between labour and electrical storms.
'We are full of electrolytes but I don't know. it's not something we've discussed as a midwific community. I can't vouch for that,' she said
She added that babies also arrived to their own agenda and their own time scale and put in an appearance when they are ready.
'Nature has its own way of preparing for labour. Before the baby comes, the body need to do some preparations and that's very important,' she said.
A royal Leo: Princess Anne, pictured presenting Prince Harry with his campaign medal, was born in August
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