Charles Spencer, the brother of Prince Harry's mum, Princess Diana, said his thoughts were with the couple.
Speaking on Lorraine, the 56-year-old said: "I can't imagine the agony for any couple for losing a child in this way. I totally agree with you – all thoughts with them today."
The BBC's BBC Home & Foreign Duty Editor, Allie Hodgkins-Brown said a "source close to Duchess of Sussex confirms to BBC Meghan is currently in good health". The source added regarding the timing of the New York Times article's release, "the couple took time to process what happened in July & having come to appreciate how common miscarriage is, wanted to talk about it publicly".
Online, celebrities, commentators and journalists were quick to respond to the article, calling Markle "brave" and "brilliant". Others said the essay could help shift the stigma around miscarriages that causes women to suffer in silence.
"This is a heartbreaking oped by Meghan, who reveals she suffered a miscarriage earlier this year. Very brave of her to share something so raw," 9 News personality Sylvia Jeffreys wrote on Twitter.
"Nearly 1 in 4 women have experienced miscarriage. Miscarriage is not a private subject," model and presenter Jessica Davies wrote. "It should be talked about more widely and openly because women should not feel like they are alone. Thank you to Meghan for sharing her pain."
"Miscarriages are far too common, heartbreakingly painful and not talked about anywhere near enough. The Duchess of Sussex should be applauded for this," David Hughes, editor of PA Media said.
Olivia Singer, the fashion news director of British Vogue called Markle a "queen".
"I can only imagine how much Meghan Markle's article will help those who have suffered a miscarriage, and found it difficult to express their grief," wrote Anila Dhami, the presenter of Channel 5 News. sands.com.au
"Her bravery to share her vulnerability will undoubtedly start a conversation and help people to open up – and seek help if needed."
"Another example of 'you never know what's going on behind closed doors'," said YouTuber Emily Canham. "It's really not that hard to be nice, you never know what someone is going through."
Markle is not the first royal woman to experience the tragedy of losing an unborn baby.
The Queen's granddaughter Zara Tindall suffered two miscarriages before having her second child.
The Countess of Wessex also lost her first baby in December 2001 when she was flown to hospital after suffering a potentially life-threatening ectopic pregnancy.
Royal family members have not yet reacted to the news. Kensington Palace, home to the Duke and Duchess of Cambridge, has been contacted for comment.