In a piece for the New York Times, the Duchess of Sussex, 39, said losing a child was something “experienced by many but talked about by few.”
Women’s organisations and charities thanked Meghan for highlighting the reality of miscarriage, with a baby loss counselling charity saying the piece would help remove the "stigma" around miscarriage.
Karen Burgess, chief executive of Petals, said: “The stigma around miscarriage prevents so many women and men reaching out for support.
"Meghan's frank, raw account of those painful moments share with us her heartbreak and help us all understand the trauma and grief miscarriage bring. We thank the Sussexes for their courage in speaking out and we hope this opens the door for more couples to feel they can do the same.”
One in four pregnancies ends in miscarriage, with most occurring before 12 weeks. There are 250,000 miscarriages every year in the UK.
Midwife Sophie King, speaking on behalf of baby loss charity Tommy’s, said: “Baby loss at any stage in pregnancy is one of the most heart-breaking things a family can experience – and as Meghan Markle said, it’s experienced by many but talked about by few.
"One in 4 pregnancies ends in loss, but it’s a real taboo in society, so mothers like Meghan sharing their stories is a vital step in breaking down that stigma and shame.
“Meghan’s essay praises the bravery of parents who share their stories, and those who prefer to grieve privately can still find comfort and connection in reading about others’ experiences. Her honesty and openness today send a powerful message to anyone who loses a baby: this may feel incredibly lonely, but you are not alone. Friends and family, doctors and midwives, all of us at support organisations like Tommy’s; we’re here.”
Last month, Chrissy Teigen, the wife of musician John Legend, was widely praised after she spoke about losing her third child, who the couple have since named Jack.
The Queen’s Granddaughter, Zara Tindall, has also previously spoken about suffering two miscarriages before having her second child.
Others reacted to Meghan’s article, with one writer describing it as “vital”.
GMB host Susanna Reid wrote: “The Duchess of Sussex writes with painful, personal insight about the truly tragic loss of miscarriage. This will be a solace to anyone who has suffered, particularly if they have found it hard to express the grief.”
BBC Historian Tessa Dunlop commented: "I was exactly Meghan’s age with one child and a younger husband when I had a miscarriage.. then another ... and another. Be kind. It’s a very lonely space."
Speaking about her own experiences, she said: “Just seeing this this morning, it was almost exactly the same. What really helped me was obviously being able to talk to you and being able to talk to other people and also Rosie, because she was only about six.nd I know that she's a lot younger than that, but that will really help having another child to focus on.”
Author Matt Haig said: “To people saying: 'why is Meghan Markle sharing her story if she doesn't want negative media attention?' It is very simple: there is a difference between sharing your own pain, and having others cause it. You have a right to your own truth. And a right to tell it. "
Haig, who was chosen by the Duchess to feature in her Forces for Change issue of Vogue, tweeted: "My wife went through a miscarriage two years ago. We were in Australia and felt alone. It was so traumatic.
“To grieve a future that wasn't there. It also felt difficult to talk about. A strange taboo. It is so healthy and healing when anyone talks about this topic so openly.”
Writer Monisha Rajesh wrote: “That Meghan Markle could write about her miscarriage knowing that it would add fuel to the fire of the demons who want her demise, makes her even more of a queen.”
Writer Jess Denham added: “Celebrities talking openly about grief and loss - especially when still taboo like miscarriage is - is vital (and I mean vital) for helping others realise they are not alone. So thank you Meghan Markle for your courageous determination to make a positive change. Heal well.”
Speaking candidly about happened, Meghan wrote: "I felt a sharp cramp. I dropped to the floor with him [her son, Archie] in my arms, humming a lullaby to keep us both calm, the cheerful tune a stark contrast to my sense that something was not right.
"I knew, as I clutched my firstborn child, that I was losing my second.
"Hours later, I lay in a hospital bed, holding my husband’s hand. I felt the clamminess of his palm and kissed his knuckles, wet from both our tears. Staring at the cold white walls, my eyes glazed over. I tried to imagine how we’d heal."
She wrote about Prince Harry’s “heartbreak” at their loss - and how she realised the first step to healing was to ask: “Are you ok?”
“Sitting in a hospital bed, watching my husband’s heart break as he tried to hold the shattered pieces of mine, I realized that the only way to begin to heal is to first ask, “Are you OK?”