The former Suits TV actress will turn 37 in August, and the two feel the ticking of her biological clock, a royal source revealed.
"Harry and Meghan want to get pregnant as quickly as possible after their wedding," the source told Radar.
"They both know that as Meghan gets older, it can be 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."
According to the royal insider, Markle and the Prince, who is younger at 33, have both seen nutritionists and doctors who specialize in giving clients diet, exercise and lifestyle programs designed to maximize couples’ chances of getting pregnant.
Markle has already said she would be prepared to look into IVF as a way of getting pregnant as soon as possible if there were signs she was having difficulty conceiving, the source said.
The insider added that while there was "no chance" Harry would have pulled out of marrying Markle if there were signs she was infertile, it "helped immensely" that she appears to be healthy and should have no trouble conceiving.
"Meghan has always looked after herself by eating healthily, and doing a lot of exercise including yoga," the source noted.
"Being in optimum health increases any woman’s chances of conceiving, and someone in Meghan’s shape should especially have no problem in that area.
"The only issue is that she knows she is heading for the big 4-0, so knows the sooner she gets pregnant the better."
Markle is believed to have consulted London-based nutritionist Melanie Brown at the end of last year, who visited the former actress in her new Kensington Palace home to give her tips on conceiving.
And it is believed that since then, Markle, and also Harry, have visited other medics and nutritionists in the run-up to their May 19 wedding.
Brown has said she focuses on "pre-conceptual and pregnancy nutrition, including weight loss and gain and immune issues."
Rumor has it that Harry has consulted nutritionist Gabriela Peacock separately from Markle for advice on slimming down for his wedding and doing everything he can to increase his fertility.
Peacock has treated royals and celebrities and has a range of cleansing supplements and vitamins that Harry is thought to now be taking "religiously," according to sources.
Prince Harry is believed to have shed at least seven pounds before his wedding. He reportedly hopes his weight loss will increase his fertility.
Both Harry and Meghan have spoken about their desire to have a family as soon as possible.
Harry has been a "fun uncle" to William and Middleton’s three kids, princes George and Louis, and Princess Charlotte.
"Of course, I would love to have kids," Harry has said. "I’m a godfather to quite a few of my friends’ children – five or six."
Months before her romance with Harry was confirmed, Markle said, "I can’t wait to start a family, but in due time."
The former TV star is so intent on having children now that the source said that's why her choice of hand rings has included emerald bands, said to aid female fertility!
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