The chances of conceiving multiple births are also increased if Meghan were to undergo IVF treatment.
Turier told The Sun, 'If you have one fertilised embryo put back, in some cases that can split into two identical monochorionic, monozygotic twins, which is why you can have one embryo put back and end up with twin.'
The loved-up couple may have been keeping mum for some time, as the royal cameraman reveals that Meghan’s placement at the back of the balcony during the Trooping the Colour celebrations on June 9 was actually a strategic move to hide any sign of a baby bump.
There are plenty of whispers going around the London media and royal staff that the couple are definitely expecting.
‘The palace is overjoyed by the news that Harry and Meghan are already expecting their first child – it’s all that anyone can talk about,’ a senior aide tells New Idea.
‘At Ascot last week and during Celia McCorquodale’s wedding, everyone was talking about the baby whispers – especially given that she was wearing such a loose, billowing dress and refused to drink any champagne on both occasions.
Harry was being so protective of her, making sure she was happy and safe – it was lovely to see,’ the source adds.
Other reports have claimed that Meghan has already been visiting fertility doctors.
'Harry and Meghan want to get pregnant as quickly as possible after their wedding,' a friend told The National Enquirer.
'They both know that as Meghan gets older, it can get increasingly harder to conceive - and they are both keenly aware of her vulnerability to health complications and the chance of miscarriage the older she gets.'
Along with fertility check-ups, Meghan also visited London-based nutritionist Melanie Brown at Kensington Palace, insiders told the Enquirer.
Brown, a 'specialist in fertility, IVF, and pregnancy,' who works out of Duke Street, gave Meghan pointers on 'pre-conceptual and pregnancy nutrition, including weight loss and gain, and immune issues.'
Harry, 33, also reportedly 'stepped up', meeting with nutritionist Gabriela Peacock on how he can drop weight and boost fertility.
If Meghan and Harry's exciting baby news is true, it will mark the first time the monarchy has welcomed twins in almost 600 years!