Meghan Markle
Meghan Markle's hair will reveal the truth if she's pregnant or not. Pictured: Markle and Enda Kenny pose with the Sentebale Polo 2018 trophy after the Sentebale Polo 2018 held at the Royal County of Berkshire Polo Club on July 26, 2018 in Windsor, England. Getty Images/Chris Jackson

Meghan Markle's fans should look at her hair from time to time to find out if she's pregnant or not.

According to Myka Meier, the Duchess of Sussex's hair is the first hint that royal fans should check to know if she's expecting or not. "The one thing that might be interesting is her hair," Meier said (via The Sun).

"We don’t know what she does to treat her hair now but it is likely she uses a keratin or a Brazilian treatment to straighten it," the etiquette expert continued. "As soon as she gets pregnant she will no longer be able to use those same products, which could be very interesting. I use the same products because I am quarter African and have very curly, frizzy hair and when I got pregnant I had to stop using all of those."

Meier said that when Markle starts to tie her hair up, it's a big sign that she's already pregnant. This is because the duchess won't be able to control her frizzy hair as she will be prohibited from using the hair products she's using now.

"I think we'll see her wearing more of a bun when that happens, which could be a tell-tale sign she is pregnant as she’ll no longer be able to use those stringent chemicals that are often used for that beautiful glossy look," she explained.

According to Dr. Sarah Jarvis, clinical director of Patient. Info, a number of moms worry about whether or not their beauty treatment products are safe to use when they're pregnant. Keratin treatment contains formaldehyde that when used in high levels can cause certain birth defects.

"So I recommend that women absolutely avoid any keratin product which might contain formaldehyde," the doctor said.

In related news, a journalist previously claimed that Prince Harry is keen on starting his own family with Markle. The Duke of Sussex is reportedly looking forward to being a dad.

"He once told me over drinks after a polo tournament in Barbados – before he had met Meghan Markle – that he often 'daydreamed' about the time he would become a father," Adam Helliker wrote.

A former royal butler echoed his thoughts. "Harry also wants a large family and wants children as quickly as possible," Paul Burrell said earlier.

However, it may be best for Prince Harry and Markle to wait until their overseas engagements are done before getting pregnant. According to National Health Services, traveling when pregnant has a higher risk of miscarriage, especially in the first trimester of pregnancy. The Duke and Duchess of Sussex are set to fly to Australia in October for the Invictus Games.