April’s Pink Moon, to appear in the skies this weekend, has some hopeful the Duke and Duchess of Sussex’s baby will be born over Easter.
Meghan and Harry have said their first born is due to arrive in late April or early May.
The new full moon - which begins on Good Friday and is known as the Pink Moon - is hoped to have an impact on the royal baby’s birth date.
The name comes not from its colour, but from the pink wildflowers that bloom in the early spring in the US and Canada.
Anecdotal evidence suggests labour can be induced by the lunar cycle and the start of a full moon.
The suggestion is that a full moon's gravitational pull affects the amniotic fluid in the same way it affects the water in the sea and rivers, as well as influencing the levels of the hormone melatonin.
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.
When the Duchess of Cambridge gave birth to Prince George on July 22 2013, it was the day of a full moon.
She went into labour with Princess Charlotte two days before a full moon, but with Prince Louis the moon was only in its first quarter.
The Pink Moon is used to fix the date of Easter, which is always the Sunday after the first full moon following the Spring Equinox.
It could be a double celebration if the baby arrives on Easter Sunday, which will also be the Queen’s birthday.
Bookmakers Coral have odds of 2/1 that the baby will be born on his or her great-grandmother the Queen's birthday on April 21 , and 5/1 that the baby will be called Elizabeth if a girl, and 6/1 Diana after Harry's late mother.
The odds are 4/1 that the royal baby will be born sometime between the Good Friday and Easter Monday bank holidays.